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Author SHA1 Message Date
Martijn Dekker
db72f41f4b Fix subshell file descriptor leak
A file descriptor (at least 3, can't reproduce for 4 and up) opened
with 'exec' or 'redirect' in a virtual/non-forked subshell survived
that subshell after exiting it:

    $ ksh -c '(redirect 3>&1); echo bug >&3'
    bug

src/cmd/ksh93/sh/io.c:
- Apply a patch from OpenSUSE (ksh93-redirectleak.dif). Source:
  https://build.opensuse.org/package/show/openSUSE:Leap:42.3:Update/ksh

src/cmd/ksh93/tests/io.sh:
- Add regression test.

Thanks to Marc Wilson for flagging this up.
2020-07-21 04:12:40 +01:00
Martijn Dekker
0c96f9749b tests/subshell.sh: fix a test for systems without /dev/fd/*
ksh's built-in test, [ and [[ commands treat /dev/fd/* specially:
e.g. 'test /dev/fd/0' returns true even if it doesn't physically
exist, as on e.g. HP-UX. However, external commands need it to
exist physically.

src/cmd/ksh93/tests/subshell.sh:
- To decide whether to run a test with 'tee', use external 'test'
  command to check if /dev/stdout and /dev/fd/1 actually exist.
2020-07-21 01:12:15 +01:00
Martijn Dekker
bc8b36faba whence -a/type -a: report both function and built-in by same name
'whence -a' is documented to list all possible interpretations of a
command, but failed to list a built-in command if a shell function
by the same name exists or is marked undefined using 'autoload'.

src/cmd/ksh93/bltins/whence.c: whence():
- Refactor and separate the code for reporting functions and
  built-in commands so that both can be reported for one name.

src/cmd/ksh93/data/builtins.c: sh_optwhence[]:
- Correct 'whence --man' to document that:
  * 'type' is equivalent to 'whence -v'
  * '-a' output is like '-v'

src/cmd/ksh93/tests/builtins.sh:
- Test 'whence -a' with these combinations:
  * a function, built-in and external command
  * an undefined/autoload function, built-in and external command

Fixes https://github.com/ksh93/ksh/issues/83
2020-07-20 21:16:24 +01:00
Martijn Dekker
01c25cb14b whence -a: fix spurious 'undefined function' message
$ ksh -c 'whence -a printf'
	printf is a shell builtin
	printf is /usr/bin/printf
	printf is an undefined function

The third line should not appear.

src/cmd/ksh93/bltins/whence.c:
- Remove faulty extra check for undefined (= autoload) functions.
  This was already handled earlier, on lines 192-193.

src/cmd/ksh93/tests/builtins.sh:
- Add regression test.
- For previous 'whence -a' test, don't bother with shell function.

Fixes https://github.com/ksh93/ksh/issues/26
2020-07-20 17:03:04 +01:00
Martijn Dekker
b2bdbef561 ksh -i: only print newline on EOF if really interactive
Some regression tests have to be run with the -i option, making the
shell behave (mostly) as if it is interactive. This causes ksh to
print a final newline upon EOF (Ctrl+D). This is functional if the
shell is really interactive, i.e. if standard input is on a
terminal and we're not running a shell script: it ensures that a
parent shell's prompt appears on a new line. But for tests like
   ksh -i -c 'testcommands'
or
   ksh -i <<EOF
   testcommands
   EOF
it's a minor annoyance. Adding an explicit 'exit' is an effective
workaround, but we might as well fix it.

src/cmd/ksh93/sh/main.c: exfile(): done:
- If shell is "interactive", only print final newline if standard
  input is on a terminal and we're not running a -c script.
2020-07-20 16:29:43 +01:00
Johnothan King
bd88cc7f4f
Fix two crashes related to kshdb (#82)
This commit fixes two different crashes related to kshdb:
- When redirect is given an invalid file descriptor, a segfault
  no longer occurs. Reproducer:
  $ ksh -c 'redirect 9>&200000000000'

- Fix a crash due to free(3) being used on an invalid pointer.
  This can be reproduced with kshdb (commands from att/ast#582):
  $ git clone https://github.com/rocky/kshdb.git
  $ cd kshdb
  $ ksh autogen.sh
  $ echo "print hi there" > $HOME/.kshdbrc
  $ ./kshdb -L . test/example/dbg-test1.sh

src/cmd/ksh93/bltins/misc.c: b_dot_cmd():
- The string pointed to by shp->st.filename must be able to be
  freed from memory with free(3), so duplicate the string with
  strdup(3).

src/cmd/ksh93/sh/io.c: sh_redirect():
- Show an error message when a file descriptor is invalid to
  fix a memory fault.
2020-07-19 23:42:12 +01:00
Martijn Dekker
36f55f1f85 bltins/whence.c: Revert accidentally included test (re: 3613da42)
Some temp debug code that tests a possible fix for #26 accidentally
snuck in to a completely unrelated commit. Sorry about that.
2020-07-19 06:42:53 +01:00
Martijn Dekker
e9c7ac70a7 remove unused 'is an exported alias' message (re: 80d9ae2b)
Commit 80d9ae2b removed the line that set the NV_EXPORT flag on an
alias when the obsolete ksh88 'alias -x' option was used. But it
turns out that flag actually did something: it caused 'whence -v'
to report the alias as an exported alias -- misleadingly, because
exported aliases have never actually exised in ksh93. Since '-x' no
longer sets that flag, that message is never printed.

src/cmd/ksh93/data/msg.c,
src/cmd/ksh93/include/path.h:
- Remove is_xalias[] = "%s is an exported alias for " message.

src/cmd/ksh93/bltins/whence.c:
- Remove dead code to check for (formerly) exported alias.
2020-07-19 06:21:14 +01:00
Martijn Dekker
5521c39a9b src/cmd/INIT/cc.darwin*: remove optimisation hacks (re: 37a9c345) 2020-07-17 22:26:51 +01:00
Martijn Dekker
37a9c34515 Optimise for small code by default
My tests with running shbench[*] on ksh binaries compiled by clang
and gcc yielded no performance difference between compiling with
'-O2' and '-Os'. So we might as well reduce ksh's size and memory
footprint by default.

[*] http://fossil.0branch.com/csb/
    https://github.com/ksh-community/shbench

src/cmd/INIT/make.probe:
- Change default gcc optimisation level from -O2 to -Os.
- Change default non-gcc optimisation level from -O to -Os.
2020-07-17 21:52:50 +01:00
Martijn Dekker
3613da4240 Remove unused libcoshell
The coshell(1) command, which is required for libcoshell to be
useful, is not known to be shipped by any distribution. It was
removed by the ksh-community fork and hence also by 93u+m (in
2940b3f5). The coshell facility as a whole is obsolete and
insecure. For a long time now, the statically linked libcoshell
library has been 40+ kilobytes of dead weight in the ksh binary.

Prior discussion (ksh2020): https://github.com/att/ast/issues/619

src/lib/libcoshell/*:
- Removed.

src/cmd/ksh93/*:
- Remove the SHOPT_COSHELL compiler option (which was enabled) and
  a lot of code that was conditional upon #ifdef SHOPT_COSHELL.

- init.c: e_version[]: Removing SHOPT_COSHELL changed the "J"
  feature identifier in ${.sh.version} to a lowercase "j", which
  was conditional upon SHOPT_BGX (background job extensions).
  But src/cmd/ksh93/RELEASE documents (at 08-12-04, on line 1188):
    | +SHOPT_BGX enables background job extensions. Noted by "J" in
    |  the version string when enabled. [...]
  That is the only available documentation. So change that "j" back
  to a "J", leaving the version string unchanged after this commit.

- jobs.c: job_walk(): We need to keep one 'job_waitsafe(SIGCHLD);'
  call that was conditional upon SHOPT_COSHELL; removing it caused
  a regression test failure in tests/sigchld.sh, 'SIGCHLD blocked
  for script at end of pipeline' (which means that until now, a ksh
  compiled without libcoshell had broken SIGCHLD handling.)

bin/package, src/cmd/INIT/package.sh:
- Don't export COSHELL variable.
2020-07-17 19:28:52 +01:00
Martijn Dekker
fbc6cd4286 Remove vestigial 3DFS support code (re: f88f302c)
Support for the long-dead 3DFS userland versioning file system was
already removed from ksh93 (although I'd overlooked some minor
things), but libast still supported it. This removes that too.

src/lib/libast/include/fs3d.h,
src/lib/libast/man/fs3d.3,
src/lib/libast/misc/fs3d.c:
- Removed.

bin/package,
src/cmd/INIT/package.sh:
- Remove attempted use of removed vpath builtin.

src/cmd/ksh93/*:
- Remove minor 3dfs vestiges.

src/lib/lib{ast,cmd,coshell}/*:
- Remove code supporting 3dfs.
2020-07-17 05:04:03 +01:00
Johnothan King
2db9953ae0
Fix three bugs in the sleep builtin (#77)
This commit backports the main changes to sh_delay from ksh93v-
and ksh2020, which fixes the following bugs:

- Microsecond amounts of less than one millisecond are no longer
  ignored. The following loop will now take a minimum of one
  second to complete:
  for ((i = 0; i != 10000; i++)) do
    sleep PT100U
  done

- 'sleep 30' no longer adds an extra 30 milliseconds to the total
  amount of time to sleep. This bug is hard to notice since 30
  milliseconds can be considered within the margin of error. The
  only reason why longer delays weren't affected is because the old
  code masked the bug when the interval is greater than 30 seconds:
  else if(n > 30)
  {
      sleep(n);
      t -= n;
  }
  This caused 'sleep -s' to break with intervals greater than 30
  seconds, so an actual fix is used instead of a workaround.

- 'sleep -s' now functions correctly with intervals of more than
  30 seconds as the new code doesn't need the old workaround. This
  is done by handling '-s' in sh_delay.

src/cmd/ksh93/bltins/sleep.c:
- Remove the replacement for sleep(3) from the sleep builtin.
- Replace the old sh_delay function with the newer one from ksh2020.
  The new function uses tvsleep, which uses nanosleep(3) internally.

src/cmd/ksh93/include/shell.h,
src/cmd/ksh93/edit/edit.c,
src/cmd/ksh93/sh/jobs.c,
src/cmd/ksh93/sh/xec.c,
src/cmd/ksh93/shell.3:
- Update sh_delay documentation and usage since the function now
  requires two arguments.

src/cmd/ksh93/tests/builtins.sh:
- Add a regression test for 'sleep -s' when the interval is greater
  than 30 seconds. The other bugs can't be tested for in a feasible
  manner across all systems:
  https://github.com/ksh93/ksh/pull/72#issuecomment-657215616
2020-07-17 05:00:28 +01:00
Johnothan King
ea5b25b93a
Fix some formatting errors, typos and other problems (#78)
Some notes:
- Removed a TODO note that was fixed in commit 43d9fbac.
- Removed a duplicate note about the '%l' time format in the changelog.
- Applied the following documentation fixes from Terrence J. Doyle:
  - https://www.mail-archive.com/ast-developers@lists.research.att.com/msg01852.html
  - https://www.mail-archive.com/ast-developers@lists.research.att.com/msg01856.html
- Fixed strange grammar in one of the error messages.
- Added missing options for rksh to the synopsis section.
- Applied a formatting fix from ksh93v- to the man page.
- Replaced a C99 line comment in src/lib/libast/comp/realpath.c with a
  proper comment that is valid in C89.
- Prioritize UTC over GMT in the documentation (missed by commit c9634e90).
- Add some extra information for 'ksh -R file' to the man page. This patch
  is from Red Hat: https://git.centos.org/rpms/ksh/blob/c8/f/SOURCES/ksh-20080202-manfix.patch
2020-07-16 22:27:00 +01:00
Johnothan King
03224ae3af
Make the 'history' and 'r' commands builtins (#76)
With this change no more preset aliases exist, so the preset alias
tables can be safely removed. All ksh commands can now be used
without 'unalias -a' removing them, even in interactive shells.
Additionally, the history and r commands are no longer limited to
being used in interactive shells.

src/cmd/ksh93/bltins/hist.c:
- Implement the history and r commands as builtins. Also guarantee
  lflag is set to one by avoiding 'lflag++'.

src/cmd/ksh93/Makefile,
src/cmd/ksh93/Mamfile,
src/cmd/ksh93/sh/main.c,
src/cmd/ksh93/sh/init.c,
src/cmd/ksh93/data/aliases.c:
- Remove the table of predefined aliases because the last few have
  been removed. During init the alias tree is now initialized the
  same way as the function tree.

src/cmd/ksh93/bltins/typeset.c:
- Remove the bugfix for unsetting predefined aliases because it is
  now a no-op. Aliases are no longer able to have the NV_NOFREE
  attribute.

src/cmd/ksh93/tests/alias.sh:
- Remove the regression test for unsetting predefined aliases since
  those no longer exist.

src/cmd/ksh93/data/builtins.c:
- Update sh_opthist[] for 'hist --man', etc.

src/cmd/ksh93/sh.1:
- Remove the list of preset aliases since those no longer exist.
- Document history and r as builtins instead of preset aliases.

Co-authored-by: Martijn Dekker <martijn@inlv.org>
2020-07-16 18:56:49 +01:00
Martijn Dekker
17f81ebedb Load 'r' and 'history' default aliases on interactive only
These two default aliases are useful on interactive shells. In
scripts, they interfere with possible function or command names.

As of this commit, these final two default aliases are only loaded
for interactive shells, leaving zero default aliases for scripts.
This completes the project to get rid of misguided default aliases.

src/cmd/ksh93/include/shtable.h,
src/cmd/ksh93/data/aliases.c:
src/cmd/ksh93/sh/init.c:
- Add empty alias table shtab_noaliases[] for scripts.
- Rename inittree() to sh_inittree() and make it external.
- nv_init(), sh_reinit(): Initialise empty alias tree for scripts.

src/cmd/ksh93/sh/main.c: sh_main():
- If interactive, reinitialise alias tree for interactive shells.

src/cmd/ksh93/tests/alias.sh:
- To test default alias removal, launch shell with -i.
2020-07-16 06:44:05 +01:00
Martijn Dekker
a42ac7e77a Fix annoying usage/--help/--man message corruption
In a locale other than C/POSIX, ksh produces corrupted usage
messages for alternatives, e.g. this output of 'typeset -\?':
| Usage: typeset [-bflmnprstuxACHS] [-a[type]] [-i[base]] <..CUT..>
|                [-T[tname]] [-Z[n]] [name[=value]...]
|    Or:[name[=value]...]
| typeset[name[=value]...]
| [[name[=value]...]
| options[name[=value]...]
| ] -f [name...]

Correct output is:
| Usage: typeset [-bflmnprstuxACHS] [-a[type]] [-i[base]] <..CUT..>
|                [-T[tname]] [-Z[n]] [name[=value]...]
|    Or: typeset [ options ] -f [name...]

Similar corruption occurs in --help and --man output.
This bug is ancient: it's already in ksh 1993-12-28 s+.

ksh2020 has this fixed. A 'git bisect' run pinpointed the fix
to this commit, which fixes the ERROR_translating macro after
removing the AST-specific locale subsystem:
https://github.com/att/ast/commit/4abc061e
But making the same change in ksh 93u+m produced no results
(probably because we have not removed that subsystem).

However, disabling the use of translation macros in optget.sh
altogether (replacing them with dummies that were already coded in
a preprocessor directive fallback for a reduced standalone libast)
turns out to work. It's not as if there is actually any translation
anyway, so this effectively fixes this bug.

The actual cause of this bug remains mysterious, but should be
somewhere in the AST translation and/or locale subsystem.

src/lib/libast/misc/optget.c:
- Use fallback translation macros.

src/cmd/ksh93/tests/builtins.sh:
- Add regression tests for output of -?, --?x, --help and --man
  for a usage string with an alternative ("Or:") usage message.
  Before the fix, these failed when running the tests in the
  C.UTF-8 locale (as in 'bin/shtests -u builtins').
2020-07-16 05:13:53 +01:00
Martijn Dekker
8c7c60ec19 shellquoting: rm redundant iswprint() call (re: f9d28935)
A regression test failure was occurring on FreeBSD for
  bin/shtests -u builtins
because UTF-8 characters were wrongly encoded as bytes in the
C.UTF-8 locale. The cause is that iswprint() always returns false
on FreeBSD if the ksh-specific C.UTF-8 locale is active, as the OS
doesn't support it.

That iswprint() call is redundant anyway; the new is_invisible()
function now handles this.

src/cmd/ksh93/sh/string.c: sh_fmtq():
- Remove redundant iswprint() test.
2020-07-16 01:13:59 +01:00
Johnothan King
01145a48dd
Handle the escape sequence for the End key (#75)
Many terminals (xterm being one example) give the Home and End keys
the escape sequences '^[[H' and '^[[F'. The first sequence is
handled in both editing modes by moving the cursor to start of
line, but ksh ignored the second sequence.

src/cmd/ksh93/edit/emacs.c,
src/cmd/ksh93/edit/vi.c:
- Add case labels for '^[[F' so that in both editing modes the End
  key moves the cursor to the end of the line.
2020-07-15 23:38:44 +01:00
Martijn Dekker
1fbbeaa19d Convert default typeset aliases to regular builtins
This converts the 'autoload', 'compound', 'float', 'functions',
'integer' and 'nameref' default aliases into regular built-in
commands, so that 'unalias -a' does not remove them. Shell
functions can now use these names, which improves compatibility
with POSIX shell scripts.

src/cmd/ksh93/data/aliases.c:
- Remove default typeset aliases.

src/cmd/ksh93/data/builtins.c,
src/cmd/ksh93/include/builtins.h:
- Add corresponding built-in command declarations. Typeset-style
  commands are now defined by a pointer range, SYSTYPESET ..
  SYSTYPESET_END. A couple need their own IDs (SYSCOMPOUND,
  SYSNAMEREF) for special-casing in sh/xec.c.
- Update 'typeset --man'.

src/cmd/ksh93/bltins/typeset.c: b_typeset():
- Recognise the new builtin commands by argv[0]. Implement them by
  inserting the corresponding 'typeset' options into the argument
  list before parsing options. This may seem like a bit of a hack,
  but it is simpler, shorter, more future-proof and less
  error-prone than manually copying and adapting all the complex
  flaggery from the option parsing loop.

src/cmd/ksh93/sh/parse.c,
src/cmd/ksh93/sh/xec.c:
- Recognise typeset-style commands by SYSTYPESET .. SYSTYPESET_END
  pointer range.
- Special-case 'compound' (SYSCOMPOUND) and 'nameref' (SYSNAMEREF)
  along with recognising the corresponding 'typeset' options.

src/cmd/ksh93/sh.1:
- Update to document the new built-ins.
- Since not all declaration commands are special built-ins now,
  identify declaration commands using a double-dagger "\(dd"
  character (which renders as '=' in ASCII) and disassociate their
  definition from that of special built-ins.

src/cmd/ksh93/tests/variables.sh:
- Adapt a regression test as there is no more 'integer' alias.
2020-07-15 20:54:06 +01:00
Martijn Dekker
45cfecfc1e tests/basic.sh: fix tests to work with xtrace (re: c5820aab) 2020-07-15 05:02:29 +01:00
Martijn Dekker
b1a4131123 Millisecond precision for 'times' builtin (re: 65d363fd, 5c677a4c)
Now that we have an iffe feature test for getrusage(3), introduced
in 70fc1da7, the millisecond-precision 'times' command from the
last version of ksh2020 can easily be backported.

src/cmd/ksh93/bltins/misc.c:
- Incorporate ksh2020 'times' command, with a couple of tweaks:
  * Use locale's radix point instead of '.'.
  * Pad seconds with initial zero if < 10.

src/cmd/ksh93/data/builtins.c:
- Update version date for 'times --man'.

src/cmd/ksh93/tests/builtins.sh:
- Update 'times' test for 3 digits after radix point.
2020-07-15 04:22:45 +01:00
Martijn Dekker
c5820aabc9 Fix $TIMEFORMAT zero-decimal and error behaviour (re: 70fc1da7)
The backported 'time' keyword code introduced a bug (shared by
ksh2020): the $TIMEFORMAT format sequences %0R, %0U and %0S output
a decimal fraction, acting as %1R, %1U and %1S.

A minor ksh2020 behaviour change that was also backported was that
the $TIMEFORMAT formatting no longer errored out on encountering an
invalid identifier, but continued. That behaviour is now reverted.

Neither of these two regressions occurred on older systems that
have to use times(3) instead of getrusage(2) or gettimeofday(2).

This commit also tweaks a regression test so that it doesn't fail
if the old times(3) interface is used.

src/cmd/ksh93/sh/xec.c: p_time():
- (Fix indentation of a for loop.)
- On modern systems, when outputting the result of $TIMEFORMAT
  format sequences, only print fraction if precision is nonzero.
- On modern systems, when encountering an invalid format sequence,
  abort formatting in the same way as done for old systems.
- On old systems, initialise 'n' in a more readable way when used
  as the index for tm[].

src/cmd/ksh93/tests/basic.sh:
- Don't fail, but issue warning on old systems that use times(3).
  Otherwise, check milliseconds: with the ksh 'sleep' builtin,
  'TIMEFORMAT=%3R; time sleep .002' should always output '0.002'.
- Change regression test for TIMEFORMAT='%0S%' to check for the
  correct output, '0%', instead of checking for an error message.
2020-07-15 02:43:35 +01:00
Johnothan King
70fc1da73e
Fix the max precision of the 'time' keyword (#72)
This commit backports the required fixes from ksh2020 for using
millisecond precision with the 'time' keyword. The bugfix refactors
a decent amount of code to rely on the BSD 'timeradd' and
'timersub' macros for calculating the total amount of time elapsed
(as these aren't standard, they are selectively implemented in an
iffe feature test for platforms without them). getrusage(3) is now
preferred since it usually has higher precision than times(3) (the
latter is used as a fallback).

There are three other fixes as well:

src/lib/libast/features/time:
- Test for getrusage with an iffe feature test rather than
  assume _sys_times == _lib_getrusage.

src/cmd/ksh93/sh/xec.c:
- A single percent at the end of a format specifier is now
  treated as a literal '%' (like in Bash).
- Zero-pad seconds if seconds < 10. This was already done for
  the times builtin in commit 5c677a4c, although it wasn't
  applied to the time keyword.
- Backport the ksh2020 bugfix for the time keyword by using
  timeradd and timersub with gettimeofday (which is used with
  a timeofday macro). Prefer getrusage when it is available.
- Allow compiling without the 'timeofday' ifdef for better
  portability.
  This is the order of priority for getting the elapsed time:
  1) getrusage (most precise)
  2) times + gettimeofday (best fallback)
  3) only times (doesn't support millisecond precision)
  This was tested by using debug '#undef' statements in xec.c.

src/cmd/ksh93/features/time:
- Implement feature tests for the 'timeradd' and 'timersub'
  macros.
- Do a feature test for getrusage like in the libast time test.

src/cmd/ksh93/tests/basic.sh:
- Add test for millisecond precision.
- Add test for handling of '%' at the end of a format specifier.
- Add test for locale-specific radix point.
2020-07-14 22:48:04 +01:00
Johnothan King
fc655f1a26
Restore 'set -b'/'set -o notify' functionality (#74)
'set -b' had no effect; it should cause the shell to notify job
state changes immediately instead of waiting for the next prompt.

This fixes a regression that was introduced in ksh93t 2008-07-25.
The bugfix is from: https://github.com/att/ast/pull/1089

src/cmd/ksh93/sh/jobs.c:
- Save the tty wait state and avoid changing it if TTYWAIT was
  already on to avoid breaking 'set -b'.
  The last 'sh_offstate' is inside of an '#if' directive because it
  is only required when ksh is compiled with SHOPT_COSHELL enabled.

src/cmd/ksh93/tests/pty.sh:
- Add a regression test for 'set -b' in interactive shells.
2020-07-14 22:00:28 +01:00
Martijn Dekker
39692fc3f6 tests/pty.sh: a couple of minor tweaks
src/cmd/ksh93/tests/pty.sh:
- init: Remove superfluous lineno=$LINENO assignments. They aren't
  needed if we avoid alias expansion on the err_exit function call.
- In the test "vi mode file name completion", append the main
  shell's PID to /tmp/fakehome to make a slightly less insecure
  temporary directory name. Unfortunately we cannot use $tmp as
  that uses $TMPDIR which may cause a false pass. (re: 4cecde1d)
2020-07-13 21:02:04 +01:00
Martijn Dekker
8ad56f90ab Add FreeBSD stty workaround for pty regression tests
Apparently, on FreeBSD, the stty command does not work correctly
for setting 'erase' or 'kill' on a pty pseudoterminal. I've no
idea whether the bug is in FreeBSD stty or in AST pty, but in any
case, a workaround is needed for the time being.

src/cmd/ksh93/tests/pty.sh:
- Save terminal state on init; set a trap to restore it on exit.
- Issue 'stty erase ^H kill ^X' on the real terminal before
  entering pty pseudoterminals.

Resolves #44.
2020-07-13 21:28:21 +02:00
Johnothan King
66c955bc8f
Fix a fork bomb when vi is run from a script and sent Ctrl-Z (#73)
This bug was reported on the old mailing list:
https://www.mail-archive.com/ast-developers@lists.research.att.com/msg00207.html

A fork bomb can occur when SIGTSTP is sent to the vi editor. Vi
must be launched from a script run with exec (tested with
BusyBox vi, nvi and vim):
$ cat /tmp/foo
vi /tmp/bar
echo end
$ ksh
$ chmod +x /tmp/foo
$ exec /tmp/foo
While in vi, send SIGTSTP using Ctrl-Z

src/cmd/ksh93/sh/fault.c:
- Only fork after Ctrl-Z if job control is available. The patch
  used checks 'job.jobcontrol' instead of 'SH_MONITOR':
  https://git.centos.org/rpms/ksh/blob/c8/f/SOURCES/ksh-20120801-forkbomb.patch
2020-07-13 19:10:23 +01:00
Martijn Dekker
84e2f6d92f tests/leaks.sh: workaround minor variation when run with shcomp
For unknown reasons, the test for a memory leak in 'read -C stat
<<< "$data"' can show an intermittent minor variation in memory
usage when run with shcomp on certain versions of macOS.

The reported variations are 48 bytes or 80 bytes. This is too small
to be the result of an actual memory leak in the tested command;
it is repeated 500 times so that any real leak should show a
difference of at least 500 bytes.

src/cmd/ksh93/tests/leaks.sh:
- Add a tolerance of 128 bytes to get rid of the false failure.

Fixes #70 (hopefully).
2020-07-10 23:01:22 +01:00
Martijn Dekker
778fd6ca2d Fix possible crash due to failure to update shell FD state
This applies ksh-20100621-fdstatus.patch from Red Hat. Not very
much information is available, so this one is more or less taken
on faith. But it seems to make sense on the face of it: calling
sh_fcntl() instead of fcntl(2) directly makes the shell update its
internal file descriptor state more frequently.

It claims to fix Red Hat bug 924440. The report is currently closed
to the public: https://bugzilla.redhat.com/show_bug.cgi?id=924440

However, Kamil Dudka at Red Hat writes:
https://github.com/ksh93/ksh/issues/67#issuecomment-656379993
| Yes, the summary of RHBZ#924440 is "crash in bestreclaim() after
| traversing a memory block with a very large size". We did not have
| any in house reproducer for the bug. The mentioned patch was
| provided and verified by a customer.

...and Marc Wilson dug up a Red Hat erratum containing this info:
https://download.rhn.redhat.com/errata/RHBA-2013-1599.html
| Previously, the ksh shell did not resize the file descriptor list
| every time it was necessary. This could lead to memory corruption
| when several file descriptors were used. As a consequence, ksh
| terminated unexpectedly. This updated version resizes the file
| descriptor list every time it is needed, and ksh no longer
| crashes in the described scenario. (BZ#924440)

No reproducer means no regression test can be added now.

src/cmd/ksh93/sh/io.c,
src/cmd/ksh93/sh/subshell.c,
src/cmd/ksh93/sh/xec.c:
- Change several fcntl(2) calls to sh_fcntl(). This function calls
  fcntl(2) and then updates the shell's file descriptor state.
2020-07-10 20:04:31 +01:00
Johnothan King
c4236cc295 Fix type names starting with lowercase 'a' (#69)
Type names that start with a lowercase 'a' cause an error when used:

$ typeset -T al=(typeset bar)
$ al foo=(bar=testset)
/usr/bin/ksh: al: : invalid variable name

The error occurs because when the parser checks for the alias
builtin (to set 'assignment' to two instead of one), only the first
letter of 'argp->argval' is checked (rather than the entire
string). This was fixed in ksh93v- by comparing argp->argval
against "alias", but in ksh93u+m the check can simply be removed
because it is only run when a builtin has the BLT_DCL flag. As of
04b9171, the alias builtin does not have that flag.

src/cmd/ksh93/sh/parse.c:
- Remove the bugged check for the alias builtin.

src/cmd/ksh93/tests/types.sh:
- Add a regression test for type names starting with a lowercase 'a'.
2020-07-10 17:54:51 +01:00
Martijn Dekker
f9d28935bb Fix UTF-8 shellquoting for xtrace, printf %q, etc.
This fixes an annoying issue in the shell's quoting algorithm
(used for xtrace (set -x), printf %q, and other things) for UTF-8
locales, that caused it to encode perfectly printable UTF-8
characters unnecessarily and inconsistently. For example:

$ (set -x; : 'aeu aéu')
+ : $'aeu a\u[e9]u'
$ (set -x; : 'aéu aeu')
+ : 'aéu aeu'
$ (set -x; : '正常終了 aeu')
+ : '正常終了 aeu'
$ (set -x; : 'aeu 正常終了')
+ : $'aeu \u[6b63]\u[5e38]\u[7d42]\u[4e86]'

This issue was originally reported by lijo george in May 2017:
https://www.mail-archive.com/ast-developers@lists.research.att.com/msg01958.html

src/cmd/ksh93/sh/string.c:
- Add is_invisible() function that returns true if a character is a
  Unicode invisible (non-graph) character, excluding ASCII space.
  Ref.: https://unicode.org/charts/PDF/U2000.pdf
- Use a fallback in is_invisible() if we cannot use the system's
  iswprint(3); this is the case for the ksh C.UTF-8 locale if the
  OS doesn't support that. Fall back to a hardcoded blacklist of
  invisible and control characters and put up with not encoding
  nonexistent characters into \u[xxxx] escapes.
  Ref.: https://unicode.org/charts/PDF/U2000.pdf
- When deciding whether to switch to $'...' quoting mode (state=2),
  use is_invisible() instead of testing for ASCII 0-127 range.
- In $'...' quoting mode, use is_invisible() to decide whether to
  encode wide characters into \u[xxxx] escapes.

src/cmd/ksh93/tests/builtins.sh:
- Add regression tests for shellquoting Arabic, Japanese and Latin
  UTF-8 characters, to be run only in a UTF-8 locale. The Arabic
  sample text[*] contains a couple of direction markers that are
  expected to be encoded into \u[xxxx] escapes.

[*] source: https://r12a.github.io/scripts/tutorial/summaries/arabic
2020-07-10 05:55:11 +01:00
Martijn Dekker
588a1ff7ca Fix spurious warning output in KIA (-R) database file
The ksh -R option creates a cross-reference database that can be
parsed with a "C Query Language" (CQL) tool.
See cql-1994.pdf at: http://gsf.cococlyde.org/files

The -R option puts ksh in noexec mode as it parses the script, and
this can produce warnings as the syntax is parsed. The bug is that
these warnings can end up in the database file, corrupting it.

This applies a fix from Paulo Andrade, via Siteshwar Vashisht:
https://www.mail-archive.com/ast-developers@lists.research.att.com/msg01952.html

src/cmd/ksh93/sh/parse.c:
- Terminate names with a zero character when writing database
  output.

A regression test is not very feasible because the majority of the
database output consists of cryptic IDs/hashes that vary depending
on the session and/or system and possibly other things.
2020-07-09 23:18:41 +01:00
Johnothan King
6930666234
Fix a syntax error when ((...)) is combined with redirections (#68)
This bugfix was backported from ksh93v- 2013-10-10-alpha.

src/cmd/ksh93/sh/parse: item():
- The done label is placed after the 'inout' call for handling I/O
  redirections. This causes the command below to produce a syntax
  error because the '>' is not handled as a redirection operator
  after 'goto done':
  $ ((1+2)) > /dev/null
  /usr/bin/ksh: syntax error: `>' unexpected
  Moving the done label fixes the syntax error as 'inout' is now
  called to handle the redirection operator.

src/cmd/ksh93/tests/arith.sh:
- Add a simple regression test.
2020-07-09 22:12:04 +01:00
Martijn Dekker
361fe1fcc3 Fix hash table memory leak when restoring PATH
There is a bug in path_alias() that may cause a memory leak when
clearing the hash table while setting/restoring PATH.

This applies a fix from Siteshwar Vashist:
https://www.mail-archive.com/ast-developers@lists.research.att.com/msg01945.html

Note that, contrary to Siteshwar's analysis linked above, this bug
has nothing directly to do with subshells, forked or otherwise; it
can also be reproduced by temporarily setting PATH for a command,
for example, 'PATH=/dev/null true', and then doing a PATH search.

Modified analysis:
ksh maintains the value of PATH as a linked list. When a local
scope for PATH is created (e.g. in a virtual subshell or when doing
something like PATH=/foo/bar command ...), ksh duplicates PATH by
increasing the refcount for every element in the linked list by
calling the path_dup() and path_alias() functions. However, when
the state of PATH is restored, this refcount is not decreased. Next
time when PATH is reset to a new value, ksh calls the path_delete()
function to delete the linked list that stored the older path. But
the path_delete() function does not free elements whose refcount is
greater than 1, causing a memory leak.

src/cmd/ksh93/sh/path.c: path_alias():
- Decrease refcount and free old item if needed.
  (The 'old' variable was already introduced in 99065353, but
  its value was never used there; this fixes that as well.)

src/cmd/ksh93/tests/leaks.sh:
- Add regression test. With the bug, setting/restoring PATH
  (which clears the hash table) and doing a PATH search 16 times
  causes about 1.5 KiB of memory to be leaked.
2020-07-09 18:34:15 +01:00
Martijn Dekker
5e7d335f2f Fix crash when listing indexed arrays with 'typeset -a'
There is a bug in print_scan() function that may cause ksh to crash
while listing indexed arrays. The crash happens in nv_search() when
called from print_scan().

This applies a fix from Siteshwar Vashist:
https://www.mail-archive.com/ast-developers@lists.research.att.com/msg01944.html

src/cmd/ksh93/bltins/typeset.c:
- Call nv_scan() without the NV_IARRAY flag, even for a null scan.

src/cmd/ksh93/tests/arrays.sh:
- Add regression test for 'typeset -a' crash and check output.
2020-07-09 16:42:16 +01:00
Martijn Dekker
a8f6d6b842 Fix crash due to double free() when sourcing multiple files
There is a bug in sh_eval() that may cause ksh to crash due to a
double free() after sourcing multiple files with '.' or 'source'
if a longjmp is triggered, e.g. by a syntax error.

This applies a fix from Siteshwar Vashist:
https://www.mail-archive.com/ast-developers@lists.research.att.com/msg01943.html

src/cmd/ksh93/sh/xec.c: sh_eval():
- Zero file descriptor io_save after closing it. This prevents a
  double free() after returning from a longjmp.

src/cmd/ksh93/tests/basic.sh:
- Add reproducer as regression test.
2020-07-09 15:35:07 +01:00
Martijn Dekker
ae92cd897e optget.c: proper formatting for '--help | --man' (re: 6916a873)
This shows a better layout in '--man' or '--nroff' output.

src/lib/libast/misc/optget.c:
- Incorporate the '--help | --man' addition in the printf format
  instead of hardcoding it in the default options string.
2020-07-09 06:21:42 +01:00
Johnothan King
9526b3fa08
Fix unexpected output from 'printf %T' with certain formats (#65)
This commit changes the behavior of four date formats accepted
by 'printf %()T' because the old behavior is not compatible with
modern implementations of date(1):
- %k and %l now return a blank-padded hour, the former based on a
  24-hour clock and the latter a 12-hour clock (these are common
  extensions present on Linux and *BSD).
- %f now returns a date with the format '%Y.%m.%d-%H:%M:%S'
  (BusyBox extension).
- %q now returns the quarter of the current year (GNU extension).

src/cmd/ksh93/data/builtins.c:
- Copy the date format documentation from date in libcmd to
  the printf man page (for documenting 'printf %T').

src/cmd/ksh93/tests/builtins.sh:
- Add four regression tests for the changed date formats.

src/cmd/ksh93/sh.1:
- Remove inaccurate information about the date formats accepted by
  printf %T'. The KornShell uses a custom version of strftime(3)
  that isn't guaranteed to accepts the same formats as the native
  strftime function.

src/lib/libast/tm/tmxfmt.c:
- Change the behavior of %f, %k, %l and %q to the common behavior.
  %k and %l are implemented as aliases to %_H and %_I to avoid
  duplicating code.

src/lib/libcmd/date.c:
- Update the documentation for the AST date command since it is
  also affected by the changes to 'printf %T'.

Fixes #62
2020-07-09 05:08:28 +01:00
Johnothan King
e70925ce10
Fix memory leak on unset of associative array (#64)
Associative arrays weren't being properly freed from memory, which
was causing a memory leak.

This commit incorporates a patch and reproducer/regress test from:
https://www.mail-archive.com/ast-users@lists.research.att.com/msg01016.html

src/cmd/ksh93/sh/name.c:
- Properly free associative arrays from memory in nv_delete().

src/cmd/ksh93/tests/leaks.sh:
- Add regression test.
2020-07-09 01:09:40 +01:00
Martijn Dekker
bf79131f40 Use vmstate for memory leak regress tests (re: ad9a9219)
'ps' does not always give reliable results; on macOS, 'ps' appears
to produce nondeterministic (i.e. randomly varying) results for
'vsz' and 'rss', making it unusable for memory leak tests. See:
https://github.com/ksh93/ksh/pull/64#issuecomment-655094931
and further comments.

So let's compile in the vmstate builtin so that we can make sure to
measure things properly. It also reports bytes instead of 1024-byte
blocks, so smaller leaks can be detected.

To be decided: whether or not to disable the vmstate builtin for
release builds in order to save about 12K in the ksh binary.

src/cmd/ksh93/data/builtins.c:
- Add vmstate to the list of builtins that are compiled in.

src/cmd/ksh93/tests/leaks.sh:
- getmem(): get size using: vmstate --format='%(busy_size)u'
  (Using busy_size instead of size seems to make more sense as it
  excludes freed blocks. See vmstate --man)
- Introduce a $unit variable for reporting leaks and set it to
  'bytes'; this makes it easier to change the unit in future.
- Since the tests are now more sensitive, initialise all variables
  before use to avoid false leak detections.
- The last test seemed to need a few more 'read' invocations in
  order to get memory usage to a steady state before the test.
2020-07-08 23:23:19 +01:00
Johnothan King
9a9da2c299
Fix use of strdup on a NULL pointer (#63)
The following set of commands can rarely cause a memory fault
when auditing[*] is enabled, although most of the time it will
simply cause ksh to write '(null)' to the auditing file in place
of a tty name:

$ [ -e /etc/ksh_audit ] || echo "/tmp/ksh_auditfile;$(id -u)" | sudo tee /etc/ksh_audit;
$ v=$(ksh  2> /dev/null +o rc -ic $'getopts a:bc: opt --man\nprint $?')
$ cat /tmp/ksh_auditfile
1000;1593599493;(null); getopts a:bc: opt --man

This happens because strdup is used unconditionally on the pointer
returned by 'ttyname', which can be NULL if stderr is closed. This
then causes 'hp->tty' to be set to null, as strdup returns NULL.
See https://github.com/att/ast/issues/1028

src/cmd/ksh93/edit/history.c:
- Make strdup duplicate 'notty' instead of NULL to prevent
  crashes.

[*] https://blog.fpmurphy.com/2008/12/ksh93-auditing-and-accounting.html
2020-07-06 21:51:44 +01:00
Martijn Dekker
300cd19987 Fix corrupt UTF-8 char processing & shellquoting after aborted read
If the processing of a multibyte character was interrupted in UTF-8
locales, e.g. by reading just one byte of a two-byte character 'ü'
(\303\274) with a command like:
	print -nr $'\303\274' | read -n1 g
then the shellquoting algorithm was corrupted in such a way that
the final quote in simple single-quoted string was missing. This
bug may have had other, as yet undiscovered, effects as well. The
problem was with corrupted multibyte character processing and not
with the shell-quoting routine sh_fmtq() itself.

Full trace and discussion at: https://github.com/ksh93/ksh/issues/5
(which is also an attempt to begin to understand the esoteric
workings of the libast mb* macros that process UTF-8 characters).

src/lib/libast/comp/setlocale.c: utf8_mbtowc():
- If called from the mbinit() macro (i.e. if both pointer
  parameters are null), reset the global multibyte character
  synchronisation state variable. This fixes the problem with
  interrupted processing leaving an inconsistent state, provided
  that mbinit() is called before processing multibyte characters
  (which it is, in most (?) places that do this). Before this fix,
  calling mbinit() in UTF-8 locales was a no-op.

src/cmd/ksh93/sh/string.c: sh_fmtq():
- Call mbinit() before potentially processing multibyte characters.
  Testing suggests that this could be superfluous, but at worst,
  it's harmless; better be sure.

src/cmd/ksh93/tests/builtins.sh:
- Add regression test for shellquoting with 'printf %q' after
  interrupting the processing of a multibyte characeter with
  'read -n1'. This test only fails in a UTF-8 locale, e.g. when
  running: bin/shtests -u builtins SHELL=/buggy/ksh-2012-08-01

Fixes #5.
2020-07-05 19:24:41 +02:00
Martijn Dekker
2624b297fc 4 typo fixes: be use => be used 2020-07-05 07:48:01 +02:00
Martijn Dekker
1ca9286ab8 tests/pty.sh: disable 'process/terminal group exercise' for now
Apparently, pty doens't handle SIGTSTP correctly:
https://github.com/att/ast/issues/375
https://github.com/ksh93/ksh/issues/45#issuecomment-653789092

src/cmd/ksh93/tests/pty.sh:
- Disable the 'process/terminal group exercise' regression test,
  which depends on correct SIGTSTP handling, until pty can be
  fixed.

Closes #45.
2020-07-04 23:31:40 +02:00
Martijn Dekker
b2382efd8b tests/shtests: rm debug command that snuck through (re: d7afb57c) 2020-07-04 17:40:07 +02:00
Johnothan King
658bba748e
Fix 'kill -INFO' on systems that support SIGINFO (#59)
src/cmd/ksh93/data/signals.c:
- SIGINFO was absent from the table of signals, which caused
  commands like 'kill -INFO $$' to fail even on platforms with
  SIGINFO (such as macOS and FreeBSD). Fix that by adding
  it to the signal table.

src/cmd/ksh93/tests/signal.sh:
- Add a regression tests for using SIGINFO with the kill builtin.
  The test will only be run if the external kill command supports
  SIGINFO.
2020-07-04 15:57:47 +01:00
Martijn Dekker
d7afb57c49 shtests: use central temporary directory; add --keep option
This gets rid of repetitive code in test scripts to create their
own temporary directories. Instead, shtests exports a $tmp to each
test script that is a subdirectory of its own temporary directory.
This has the advantage of having all test script temporary
directories in one hierarchy. Along with a new option to keep
temporary files, this makes it easy to inspect them if wanted.

This does make the test scripts less self-contained as they now
depend on a temporary directory being exported as $tmp. But they
already depended on $SHELL being the shell to test, so they already
were not quite self-contained.

src/cmd/ksh93/tests/shtests:
- Add -k/--keep option to keep temporary directory. Make the EXIT
  trap report its location instead of deleting it.
- For each test, create a subdirectory of $tmp (named after the
  test script plus the tested locale or 'shcomp') and export that
  subdirectory to the test script as its own $tmp.
- If -k is not given, delete each script's temporary files
  immediately after running it to minimise disk usage.

src/cmd/ksh93/tests/*.sh:
- Don't make own temp directory.
- Refuse to run if $tmp is not set.
- Miscellaneous tweaks.
2020-07-04 01:28:08 +02:00
Martijn Dekker
fa70fc3f77 tests/pty.sh: misc tweaks
src/cmd/ksh93/tests/pty.sh:
- Fix race condition in the test "raw Bourne mode literal tab
  characters with wide characters enabled" by adding 'd 10' to add
  a 10-millisecond delay before every write. Thanks to @JohnoKing:
  https://github.com/ksh93/ksh/pull/57#issuecomment-653617531
- Fix locale for test "raw Bourne mode backslash handling" (should
  be UTF-8, not UTF8) (re: a0dcdeea).
- Add a few more dummy # err_exit # comments to allow shtests to
  count the number of tests.
2020-07-03 21:59:58 +02:00
Johnothan King
a0dcdeeade Fix bugs with backslash escaping in interactive vi mode (#57)
This commit fixes the following bugs in the 'vi' editing mode
backslash escape feature. Ref.: Bolsky & Korn (1995), p. 113, which
states for \: "Similar to Control+V [...] except that it escapes
only the next Erase or Kill charactrer".

1. The vi mode now only escapes the next character if the last
   character input was a backslash, fixing the bug demonstrated at:
   https://asciinema.org/a/E3Rq3et07MMQG5BaF7vkXQTg0
2. Escaping backslashes are now disabled in vi.c if the vi mode is
   disabled (note that vi.c handles raw editing mode in UTF-8
   locales). This makes the behavior of the raw editing mode
   consistent in C/POSIX and UTF-8 locales.
3. An odd interaction with Backspace when the character prior to a
   separate buffer entered with Shift-C was a backslash has been
   fixed. Demonstration at: https://asciinema.org/a/314833
   ^? will no longer be output repeatedly when attempting to erase
   a separate buffer with a Backspace, although, to be consistent
   with vi(1), you still cannot backspace past it before escaping
   out of it. Ref.:
   https://github.com/ksh93/ksh/issues/56#issuecomment-653586994

src/cmd/ksh93/edit/vi.c:
- Prevent a backslash from escaping the next input if the previous
  input wasn't a backslash. This is done by unsetting a variable
  named backslash if a backslash escaped a character. backslash is
  set to the result of c == '\\' when the user enters a new
  character.
- Disable escaping backslashes in the raw editing mode because
  it should not be enabled there.

src/cmd/ksh93/tests/pty.sh:
- Add some tests for how ksh handles backslashes in each
  editing mode to test for the bugs fixed by this commit.

Fixes #56.
2020-07-03 21:15:21 +02:00
Anuradha Weeraman
035a4cb3f4
Fix segfault if $PATH contains a .paths directory (#55)
ksh crashed if it encountered a .paths directory in any of the
directories in $PATH.

Ref: https://bugs.launchpad.net/ubuntu/+source/ksh/+bug/1534855

src/cmd/ksh93/sh/path.c: path_chkpaths():
- Refuse to read .paths if it's not a regular file
  or a symlink to a regular file.
2020-07-02 23:29:07 +01:00
Martijn Dekker
0c40e7c182 INIT/make.probe: change for GCC v10 based on official AST repo
In <https://github.com/att/ast/commit/d2771913>, GCC version 10 was
specifically special-cased for skipping the -nostartfiles flag
along with versions 7, 8, and 9. It seems more future-proof to
specifically include it for versions up to 6 and remove it for any
version 7 and up.

src/cmd/INIT/make.probe:
- Remove the -nostartfiles for all version of gcc > 7.
2020-07-03 00:16:37 +02:00
Johnothan King
db1d539d49
Fix ERE repetition expressions in [[ ... =~ ERE{x,y} ]] (#54)
Regular expressions that combine a repetition expression with
a parenthesized sub-expression throw a garbled syntax error:

$ [[ AATAAT =~ (AAT){2} ]]
ksh: syntax error: `~(E)(AAT){2} ]]
:'%Cred%h%Creseksh: syntax error: `~(E)(AAT){2} ]]
:'%Cred%h%Creseksh: syntax' unexpected

The syntax error occurs because ksh is not fully
accounting for '=~' when it runs into a curly bracket.
This fix disables the syntax error when the operator
is '=~' and adds handling for '(str){x}' (to allow for
more than one sub-expression). This bugfix and the
regression tests for it were backported from ksh93v-
2014-12-24-beta.

src/cmd/ksh93/sh/lex.c:
- Do not trigger a syntax error for '{x}' when the operator
  is '=~' and add handling for multiple parentheses when
  combined with '{x}'.

src/cmd/ksh93/tests/bracket.sh:
- Add two tests from ksh93v- to test sub-expressions
  combined with the '{x}' quantifier.
2020-07-02 18:40:15 +01:00
Johnothan King
ad9a9219f0
Fix memory leak regression tests by using ps(1) (#50)
src/cmd/ksh93/tests/leaks.sh:
- This script was never actually running the regression
  tests because 'vmstate' isn't available as a builtin.
  While this can be fixed by adding vmstate to the builtin
  table, that has the downside of increasing the binary
  size of ksh. This commit replaces all usage of 'vmstate'
  with 'ps' and 'awk' as a different way to measure
  memory usage. The memory leaks regression tests are now
  always run.
- Rename old $n to $N due to new $n interfering with the old
  regression test.
- Add before and after results for the number of 1024-byte
  blocks leaked in each test.

Co-authored-by: Martijn Dekker <martijn@inlv.org>
2020-07-01 20:00:58 +01:00
Johnothan King
120aec25ba
Fix a crash when 'read -u' is given an invalid fd (#53)
File descriptors that are too far out of range will cause the
read builtin to crash. The following example will generate
two crashes:

$ ksh -c 'read -u 2000000' || ksh -c 'read -u-2000000'

The fix is to error out when the given file descriptor is out
of range. This bugfix is from Tomas Klacko, although it was
modified to use 'sh_iovalidfd' and reject numbers greater
than 'INT_MAX':
https://www.mail-archive.com/ast-developers@lists.research.att.com/msg01912.html
The question about 'shp->fdstatus[-1]' only applies to ksh93v-
(ksh93u+ doesn't have any references to 'shp->fdstatus[-1]').

src/cmd/ksh93/bltins/read.c:
- File descriptors that are out of range should be rejected
  with an error message (like invalid file descriptors that
  are in range). The seemingly redundant check for negative
  numbers is there because out of range negative numbers also
  cause memory faults despite the later 'fd<0' check.

src/cmd/ksh93/tests/io.sh:
- Add three tests for attempting 'read -u' on various invalid
  file descriptor numbers.
2020-07-01 18:14:10 +01:00
Martijn Dekker
3e14072768 package.sh: clean up FIFO properly (re: 936802f9)
Not cleaning up the FIFO broke 'grep -r' in the arch directory,
making it hang forever. So we need a better way of cleaning it up.

bin/package,
src/cmd/INIT/package.sh:
- Unlink the FIFO early after sleeping a second in the background.
  This works because the named directory entry is only needed to
  establish the pipe, not to keep it going.
2020-06-30 04:45:02 +02:00
Martijn Dekker
8d8a825723 Part-revert GMT->UTC change (re: c9634e90)
To get ksh to prefer UTC over GMT in 'printf %T' output, only the
change in format[] was needed. The corresponding change in zone[]
made it prefer UTC for London time, even in summer time, which is
wrong -- e.g.:

$ LANG=C TZ=Europe/London arch/*/bin/ksh -c 'date; printf %T\\n now'
Tue Jun 30 01:39:09 BST 2020
Tue Jun 30 00:39:09 UTC 2020

src/lib/libast/tm/tmdata.c:
- Revert change in zone[].
2020-06-30 02:46:47 +02:00
Martijn Dekker
fa51a5ce3b Fix 'whence -a' regression test (re: 99065353)
The regression test failed on systems where 'chmod' exists at more
than one location, e.g. Slackware where it's at both /bin/chmod and
/usr/bin/chmod.

src/cmd/ksh93/tests/builtins.sh: 'whence -a'/tracked aliases test:
- In the expected value, use modified 'whence -a -p chmod' output
  to get all of the paths to chmod.
- On failure, report both expected and actual values.
2020-06-30 01:43:25 +02:00
Johnothan King
1b5bc1802a
Fix the readonly builtin's scope in functions (#51)
* Fix the readonly builtin's scope in functions

This bug was first reported at https://github.com/att/ast/issues/881

'tdata.sh->prefix' is only set to the correct value when
'b_readonly' is called as 'export', which breaks 'readonly' in
functions because the correct scope isn't set. As a result, the
following example will only print a newline:

$ function show_bar { readonly foo=bar; echo $foo; }; show_bar

The fix is to move the required code out of the if statement for
'export', as it needs to be run for 'readonly' as well. This bugfix
is from https://github.com/att/ast/pull/906

src/cmd/ksh93/bltins/typeset.c:
- Set 'tdata.sh->prefix' to the correct value, otherwise 'readonly'
  uses the wrong scope.

src/cmd/ksh93/tests/builtins.sh:
- Add the regression test from ksh2020, modified to run in a
  subshell.

src/cmd/ksh93/data/builtins.c,
src/cmd/ksh93/sh.1:
- Add documentation of 'readonly' vs. 'typeset -r' difference:
  'readonly' does not create a function-local scope.

Co-authored-by: Martijn Dekker <martijn@inlv.org>
2020-06-29 19:09:20 +01:00
Johnothan King
10b6ba801d
Fix memory corruption when a compound variable is unset (#49)
The following set of commands ends with a memory fault under
certain circumstances because ksh attempts to free memory
twice, causing memory corruption:

$ testarray=(1 2)
$ compound testarray
$ unset testarray
$ eval testarray=

The fix is to make sure 'np->nvfun' is a valid pointer before
attempting to free memory in 'put_tree'. This patch is from
OpenSUSE: https://build.opensuse.org/package/view_file/shells/ksh/ksh93-nvtree-free.dif?expand=1

src/cmd/ksh93/sh/nvtree.c:
- Do not try to free memory when 'np->nvfun' and 'val'
  are false.

src/cmd/ksh93/tests/comvar.sh:
- Add a regression test for the double free problem. The
  reproducer must be run from an executable script
  with 'ksh -c'.
2020-06-29 18:08:28 +01:00
Johnothan King
5135cf651c
Fix crashes caused by 'typeset -RF' (#47)
Variables created with 'typeset -RF' were being treated as
short integers, even though they are actually floating point
values. As a result the following example will cause a crash:

$ typeset -RF foo=1
$ test "$foo"

This is fixed by checking for 'NV_DOUBLE' with 'nv_isattr',
which prevents ksh from treating floating point values as
short integers due to '== NV_INT16P' excluding 'NV_DOUBLE'.
This bugfix was backported from ksh93v- 2013-10-10-alpha.

src/cmd/ksh93/sh/array.c,
src/cmd/ksh93/sh/name.c,
src/cmd/ksh93/sh/nvdisc:
- Avoid treating floating point values as short integers by
  checking for 'NV_DOUBLE' with 'nv_isattr'.

src/cmd/ksh93/tests/types.sh:
- Add a regression test for the 'typeset -RF' crash. The
  crash cannot be replicated if 'typeset -RF' sets 'foo'
  to zero.
2020-06-28 23:30:27 +01:00
Martijn Dekker
c870be9fea regress: avoid interference from systemwide /etc/ksh.kshrc
ksh, even non-interactive, loads /etc/ksh.kshrc by default. On
some systems this can be a problem, e.g. OpenBSD, which installs a
default /etc/ksh.kshrc which is designed for its version of pdksh.

Quoth sh.1:

    On systems that support a system wide /etc/ksh.kshrc
    initialization file, if the filename generated by the expansion
    of ENV begins with /./ or ././ the system wide initialization
    file will not be executed.

src/cmd/ksh93/tests/shtests,
src/cmd/ksh93/tests/builtins.sh,
src/cmd/ksh93/tests/options.sh,
src/cmd/ksh93/tests/pty.sh:
- Instead of emptying or unsetting ENV, ensure it is exported with
  a default value of /./dev/null so we skip loading the system-wide
  profile and load an empty user profile.
- Where a specific ENV path was required for the tests, prefix it
  with '/.' so it starts with '/./'.
2020-06-27 00:52:17 +02:00
Johnothan King
bb4745e897
Fix incorrect behavior of 'cd ../.foo' (#46)
The cd builtin was removing '.' from directory names when combined
with a preceding '../', which caused commands like 'cd ../.local'
to become 'cd ../local'. This patch fixes the problem by limiting
the extra handling to leading '..'. The bugfix comes from ksh93v-
2013-10-10-alpha, although this version is a shortened patch from
Solaris (as ksh93v- refactored a decent amount of the code for the
cd builtin).

src/cmd/ksh93/bltins/cd_pwd.c:
- cd should only check for leading '..', as trying to handle a lone
  '.' only causes problems.

src/cmd/ksh93/tests/builtins.sh:
- Add a regression test for this problem based on the test present in
  ksh93v- 2013-10-10-alpha.

Patch from Solaris:
https://github.com/oracle/solaris-userland/blob/860d27f/components/ksh93/patches/270-23319761.patch
2020-06-26 23:36:29 +01:00
Martijn Dekker
eaaa0de74d tests/builtins.sh: change GMT to UTC before testing (re: c9634e90)
Apparently some systems are still configured to use GMT instead of
UTC after all. This included our own GitHub CI runner config.
Oops. This made the previous commit fail to pass the CI test run.

We can't win this one, it's got to be either one or the other.
UTC is the international standard on which civil time is based.
GMT is often taken as synonymous for UTC, but in navigation,
it can differ from UTC by up to 0.9 seconds. Ref.:
https://en.wikipedia.org/w/index.php?title=Greenwich_Mean_Time&oldid=963422787
The more ambiguous term should not be the first preference.

src/cmd/ksh93/tests/builtins.sh:
- Before checking 'printf %T now' output against 'date' output,
  change any ' GMT ' in the latter to ' UTC '.

.github/workflows/ci.yml:
- Set time zone to UTC, not GMT.
2020-06-26 13:42:06 +02:00
Martijn Dekker
c9634e908d tmdata: prioritise "UTC" over "GMT"
"UTC" is the modern name for what used to be "GMT", but ksh still
preferred GMT. On systems configured to use the UTC time zone, this
caused a 'printf %T' regression test failure in tests/builtins.sh
as the external 'data' utility will prefer UTC these days.

src/lib/libast/tm/tmdata.c:
- Reorder the name alternatives for UTC/GMT so that UTC is
  the first preference.

src/cmd/ksh93/tests/builtins.sh:
- Report expected and actual values on 'printf %T' failure.

Related: #6
2020-06-26 13:25:40 +02:00
Martijn Dekker
8c705bf3b7 Fix behaviour of tabs in raw Bourne Shell-like editing mode
When neither '-o emacs' nor '-o vi' is active, there were a couple
of bugs with entering tab characters:
1. Tab completion was erroneously left active. The cause of this
   was that raw Bourne edit mode is handled by ed_viread() in vi.c
   on shells with wide character support, instead of the default
   ed_read() in edit.c, and the former failed to check if vi mode
   is active when processing tab characters.
2. When entering literal tab characters, the cursor was moved to
   the right only one character, instead of the amount of
   characters corresponding to the tab.

src/cmd/ksh93/edit/vi.c: getline():
- Before processing '\t' (tab) for command completion, check that
  the 'vi' shell option (SH_VI) is active.

src/cmd/ksh93/edit/edit.c: ed_virt_to_phys():
- When translating literal tabs to on-terminal spaces and when
  recalculating the cursor position, remove erroneous checks for
  SH_VI; this is also needed in raw Bourne mode. According to my
  own testing, this has no effect on emacs mode (knock on wood).

src/cmd/ksh93/tests/pty.sh:
- Add two regression tests. An odd race condition reveals itself in
  either pty or in ksh's raw/Bourne edit mode; see comment in test.
  Effect is we have to expect either literal tabs or tabs expanded
  to spaces, until that is tracked down and fixed.

Fixes #43.
2020-06-26 11:34:02 +02:00
Johnothan King
4cecde1dd3 Fix buggy completion of ~/some in vi mode (#41)
This commit fixes the bug reported in:
https://github.com/att/ast/issues/682
The following sequence fails in vi mode because ksh looks in the
wrong part of the 'virtual' buffer:

$ touch ~/testfile
$ ls ~/test<tab>

The fix is to change 'virtual[i]' to 'virtual[last_virt]' in the
bugged section of code. The other changes are to make sure listing
files in a directory with something like 'ls /etc/<tab>' calls the
code for Ctrl+L to preserve 'ls /etc/' rather than try (and fail)
to complete the directory name, producing 'ls /etc\n/'. This bugfix
was backported from ksh93v- 2013-10-10-alpha.

src/cmd/ksh93/edit/vi.c
 - Backport the bugfix from ksh93v- 2013-10-10-alpha for this
   problem.

src/cmd/ksh93/tests/pty.sh
 - Add a regression test for this issue using pty, adjusted slightly
   for a fake home directory in /tmp.
2020-06-25 23:13:45 +02:00
Johnothan King
d41ec674c7 Fix some errors in the documentation and other minor issues (#42)
Somewhat notable changes in this commit:
- The 'set +r' bugfix (re: 74b41621) is now documented in the
  changelog.
- Missing options have been added to the synopsis section of the
  ksh man page.
- The minor formatting fix from https://github.com/ksh-community/ksh/pull/5
  has been applied to the ksh man page.
- A few fixes from https://github.com/att/ast/commit/5e747cfb
  have been applied to the ksh man page.
- The man page fixes from https://github.com/att/ast/pull/353
  have been applied, being:
  - An addition to document the behavior of 'set -H'.
  - A fix for the cd section appending rksh93.
  - A fix for some options being indented too far.
  - Removal of a duplicate section documenting '-D'.
  - Reordering the options for 'set' in alphabetical order.
  - A minor fix for the documentation of 'ksh -i'.
2020-06-25 19:31:51 +02:00
Martijn Dekker
43d9fbac1f tests/bracket.sh: disable 'test -N' tests due to noatime mounts
src/cmd/ksh93/tests/bracket.sh:
- Disable tests for [[ -N ... ]] (test -N ...), because it is
  expected to break on systems where $TMPDIR (or even the entire
  root file system) is mounted with noatime for better performance.
  Ref.: https://opensource.com/article/20/6/linux-noatime
  (It also needs annoyingly long sleep times on older systems with
  a 1-second timestamp granularity.)
2020-06-25 14:28:37 +02:00
Martijn Dekker
2315f6687a Add regress test for fixed BUG_KUNSETIFS (re: 6f0e008c, 7b994b6a)
Modernish is no longer detecting BUG_KUNSETIFS, as I've just
discovered. Always nice when bugs spontaneously vanish...

A 'git reset HEAD~1'/recompile/retest loop reveals this bug was
fixed by 6f0e008c, as later modified by 7b994b6a.

So, let's make sure it stays fixed.

src/cmd/ksh93/tests/variables.sh:
- Add a couple of regression tests for BUG_KUNSETIFS presence,
  detection and known workaround, based on the same in modernish.
  Ref.: https://github.com/modernish/modernish/blob/3ddcbd13/lib/modernish/cap/BUG_KUNSETIFS.t
	https://github.com/modernish/modernish/blob/3ddcbd13/lib/modernish/tst/isset.t#L204-L222
2020-06-24 20:00:01 +02:00
Martijn Dekker
43c09c2d6f tests/pty.sh: disable 137(C) because it actually tests vi(1)
Testing the behaviour of an external editor, even the standard one,
is outside the scope of the ksh regression tests.

src/cmd/ksh93/tests/pty.sh:
- Disable a test that invoked vi(1) and that failed, either
  intermittently or consistently, on too many systems because
  whatever vi(1) is installed locally doesn't write the string
  "/tmp/" exactly as and/or when expected.
2020-06-24 16:40:28 +02:00
Martijn Dekker
5c677a4c6c Refactor the new 'times' builtin; zero-pad seconds (re: 65d363fd)
The output format is now identical to mksh's except for
the locale-dependent radix point ('.' or ',').

src/cmd/ksh93/bltins/misc.c:
- Output format tweak: pad seconds with initial zero if < 10.
- Use "too many operands" (e_toomanyops) error msg from 3ba4900e
  if there are operands, instead of "bad syntax" (e_badsyntax).
- Consolidate repetitive calculating and printing code
  into print_times().
- Get rid of some excessive variables.

src/cmd/ksh93/tests/builtins.sh:
- Update regression tests to match the above.

src/cmd/ksh93/data/builtins.c:
- Update sh_opttimes[] version string.
2020-06-24 14:32:20 +02:00
Martijn Dekker
57ff4676eb Fix very silly bug in times builtin (re: 65d363fd)
Well, that's what I get for backporting code without properly
checking it over. There was an elementary math error in how the
times builtin calculated seconds:
	utime_sec = utime - utime_min;
which could cause output such as "1m98.38s" or "3m234.77s".

src/cmd/ksh93/bltins/misc.c: b_times():
- Use fmod(), i.e. floating point modulus, to calculate seconds.
2020-06-24 07:47:57 +02:00
Martijn Dekker
d8fe061f4c shtests: count nonexistent tests as errors (re: c2eabc57)
When a nonexistent test script was given as an argument to
shtests, this was not counted as an error and shtests exited
successfully (with status 0).

src/cmd/ksh93/tests/shtests:
- Increase total error count if a test script is not found.
2020-06-24 00:53:59 +02:00
Johnothan King
0aa9e03f55
Fix process substitution combined with redirection (#40)
The code for handling process substitution with redirection was
never being run because IORAW is usually set when IOPROCSUB is
set. This commit fixes the problem by moving the required code
out of the !IORAW if statement. The following command now prints
'good' instead of writing 'ok' to a bizzare file:

$ ksh -c 'echo ok > >(sed s/ok/good/); wait'
good

This commit also fixes a bug that caused the process ID of the
asynchronous process to print when the shell was in interactive
mode. The following command no longer prints a process ID,
behaving like in Bash and zsh:

$ echo >(true)
/dev/fd/5

src/cmd/ksh93/sh/args.c:
 - Temporarily turn off the interactive state while in a process
   substitution to prevent the shell from printing the PID of
   the asynchronous process.

src/cmd/ksh93/sh/io.c:
 - Move the code for process substitution with redirection into
   a separate if statement.

src/cmd/ksh93/tests/io.sh:
 - Add two tests for both process substitution bugs fixed by this
   commit.

src/cmd/ksh93/tests/shtests:
 - Update shtests with a patch from Martijn Dekker to use
   pretty-printing for the output from the times builtin (if it
   is available).

Fixes #2
2020-06-23 23:02:16 +01:00
Johnothan King
c1994b87f1
Fix nested functions ignoring prefixed variable assignments (#37)
This commit fixes the bug described in att/ast#32. The fix and
following explanation is from att/ast#467:

While copying variables from function's local scope to a new scope,
variable attributes were not copied. Such variables were not marked
to be exported in the new function. For e.g.

function f2 { env | grep -i "^foo"; }
function f1 { env | grep -i "^foo"; f2; }
foo=bar f1

prints 'foo=bar' only once, but it should print be twice.

src/cmd/ksh93/sh/xec.c:
 - When variables from the local scope of a function are copied into
   the scope of a nested function, the attributes of the variables
   need to be copied as well.

src/cmd/ksh93/tests/functions.sh:
 - Add regression tests from ksh2020 to check environment variables
   passed to functions.
2020-06-23 00:27:05 +01:00
Johnothan King
e0b326ae15
Fix a test failure for printf %T now on Linux (#38)
src/cmd/ksh93/tests/builtins.sh:
 - The output of 'printf %T now' and the external 'date'
   command aren't guaranteed to be the same unless $LC_ALL
   is set to 'C'. Set LC_ALL in these command substitutions
   to fix a spurious test failure on Linux.
2020-06-22 23:55:51 +01:00
Johnothan King
ff358f3464 Fix a crash when 'kill %%' and 'kill %+' are run (#35)
Ksh was trying to use the 'pw' variable as a valid pointer even
when it was NULL. This is fixed by doing the error check for
'pw' before doing anything else in 'job_kill'.

This bugfix is from Red Hat:
44e0a643a9/f/SOURCES/ksh-20130214-fixkill.patch

Fixes #34
2020-06-22 19:11:49 +02:00
Martijn Dekker
3ba4900e9c Make 'stop' and 'suspend' regular built-ins
The 'stop' and 'suspend' default aliases are now converted into
regular built-in commands so that 'unalias -a' does not remove
them, 'suspend' can do some sanity checks, and something like
	cmd=stop; $cmd $!
will now work.

src/cmd/ksh93/bltins/trap.c:
- b_kill(): Incorporate 'stop' functionality, which is simply
  setting the same flag and variable as '-s STOP' would have done.
- b_suspend(): Add simple builtin function that sends SIGSTOP to
  the main shell. Check for no operands, and refuse to suspend a
  login shell (which would leave the user stuck with no way out).
  Also check that 'kill' succeeds; if we're in an asynchronous
  subshell, it is possible the main shell no longer exists.

src/cmd/ksh93/data/aliases.c:
- Remove "stop" and "suspend" default aliases. (Why were these
  conditional upon SIGTSTP when they actually issued SIGSTOP?)

src/cmd/ksh93/include/builtins.h,
src/cmd/ksh93/data/builtins.c,
src/cmd/ksh93/data/msg.c:
- Add declarations of "stop" and "suspend" regular built-ins.
- Add option strings (AST manual/--man pages) for them.
- Add e_toomanyops ("too many operands") reusable error message for
  b_suspend(). Other new commands may want this at some point.

src/cmd/ksh93/sh.1:
- Remove "stop" and "suspend" default aliases.
- Document "stop" and "suspend" regular built-in commands.
2020-06-22 15:36:29 +02:00
Anuradha Weeraman
54da7fc202
Fix 'bin/package clean' deleting entire git repo (#32)
This appears to be originating from:

2755         *)      if      test ! -d $INSTALLROOT
2756                 then    INSTALLROOT=$PACKAGEROOT;

where INSTALLROOT=PACKAGEROOT and 'clean' deletes everything under
INSTALLROOT thus deleting the entire git repo. This only applies when
there's no arch/$HOSTTYPE directory due to the condition above.

bin/package,
src/cmd/INIT/package.sh:
- Delete arch/$HOSTTYPE as stated in the documentation
  for the clean action instead of $INSTALLROOT.
2020-06-22 00:59:55 +01:00
Anuradha Weeraman
de2b4a6f97
edit/edit.c: fix compiler warnings (#31)
This fixes compiler warnings for implicit-ints:
warning: return type defaults to 'int' [-Wimplicit-int]
 1854:     sh_tcgetattr(int fd, struct termios *tty)
 1863:     sh_tcsetattr(int fd, int cmd, struct termios *tty)

cmd/ksh93/edit/edit.c:
- Set the return type explicitly to int and align with the prototype
  declared in include/terminal.h.
2020-06-21 01:47:11 +01:00
Martijn Dekker
9d428f8f5e Fix erroneous fork after 'readonly PATH' in subshell (re: 102868f8)
After making PATH readonly in a virtual subshell (without otherwise
changing it, so the subshell is never forked), then the main shell
would erroneously fork into a background process immediately after
leaving the virtual subshell. This was caused by a bug in the
forking workaround that prevents changes in PATH in a virtual
subshell from clearing the parent shell's hash table.

src/cmd/ksh93/sh/name.c: nv_putval():
- If we're either setting or restoring PATH, do an additional check
  for the NV_RDONLY flag, which means the function was told to
  ignore the variable's readonly state. It is told to ignore that
  when restoring the parent shell state after exiting a virtual
  subshell. If we don't fork then, we don't fork the parent shell.

src/cmd/ksh93/tests/subshell.sh:
- Add regression test verifying that no forking happens when making
  PATH readonly in a subshell.

Fixes #30.
2020-06-20 23:47:42 +02:00
Johnothan King
bd3e2a8001
Fix unreliable behavior when special vars are readonly or unset (#27)
src/cmd/ksh93/data/variables.c:
 - Running 'unset .sh.lineno' creates a memory fault, so fix that
   by giving it the NV_NOFREE attribute. This crash was happening
   because ${.sh.lineno} is an integer that cannot be freed from
   memory with free(3).

src/cmd/ksh93/sh/init.c:
 - Tell _nv_unset to ignore NV_RDONLY when $RANDOM and $LINENO are
   restored from the subshell scope. This is required to fully
   restore the original state of these variables after a virtual
   subshell finishes.

src/cmd/ksh93/bltins/typeset.c,
src/cmd/ksh93/sh/subshell.c:
 - Disabled some optimizations for two instances of 'sh_assignok' to
   fix 'readonly' in virtual subshells and '(unset .sh.level)' in
   nested functions. This fixes the following variables when
   '(readonly $varname); enum varname=' is run:

   $_
   ${.sh.name}
   ${.sh.subscript}
   ${.sh.level}

   The optimization in question prevents sh_assignok from saving the
   original state of these variables by making the sh_assignok call
   a no-op. Ksh needs the original state of a variable for it to be
   properly restored after a virtual subshell has run, otherwise ksh
   will simply carry over any new flags (being NV_RDONLY in this case)
   from the subshell into the main shell.

src/cmd/ksh93/tests/variables.sh:
 - Add regression tests from Martijn Dekker for setting special
   variables as readonly in virtual subshells and for unsetting
   special variables in general.

Fixes #4
2020-06-20 18:08:41 +01:00
Anuradha Weeraman
ee698e89d5
Fix compiler warning in INIT/ratz.c (#28)
src/cmd/INIT/ratz.c:
- Fix build warning:

  src/cmd/INIT/ratz.c:4741:2: warning: case label value exceeds maximum value for
   type
   4741 |  case 0241:
        |  ^~~~

  The character literal in the switch expression was being treated
  as a signed char while the case label 0241 is greater than 127,
  resulting in this warning.
2020-06-20 12:42:53 +01:00
Johnothan King
99065353b3 Fix 'whence -a' to print correct path for tracked alias (#25)
'whence -a' bases the path for tracked aliases on the user's
current working directory if an enabled ksh builtin of the same
name is also available. The following example will claim 'cat'
is in the user's current working directory:

$ whence -a cat
cat is a tracked alias for /usr/bin/cat
$ builtin cat
$ whence -a cat
cat is a shell builtin
cat is /usr/bin/cat
cat is a tracked alias for /current/working/directory/cat

This patch from ksh2020 fixes this problem by properly saving the
path of the tracked alias for use with 'whence -a', since
'path_pwd' (as implied by the function's name) only gets the users
current working directory, not the location of tracked aliases.
Ref.: https://github.com/att/ast/issues/1049

This bug was originally reported by David Morano about two decades
ago to the AST team: https://github.com/att/ast/issues/954

src/cmd/ksh93/bltins/whence.c:
 - Print the actual path of a tracked alias, path_pwd doesn't
   have this functionality.

src/cmd/ksh93/include/name.h:
 - Add 'pathcomp' for saving the value of tracked aliases.

src/cmd/ksh93/sh/path.c:
 - Save the value of tracked aliases for use by whence.

src/cmd/ksh93/tests/builtins.sh:
 - Add a regression test for using 'whence -a' on tracked
   aliases with a builtin equivalent.
2020-06-19 14:03:58 +02:00
Martijn Dekker
876da711c0 data/builtins.c: fix typo in 'getopts' usage message 2020-06-18 12:12:15 +02:00
Martijn Dekker
57af42d968 data/builtins.c: tweaks for {exec,redirect} --man (re: 7b82c338)
src/cmd/ksh93/data/builtins.c:
- sh_optexec[], sh_optdirect[]: Move paragraphs on exit behaviour
  to the EXIT STATUS section, where people would look for them.
- sh_optexec[]: Since we modified b_exec() to support 'redirect',
  add "ksh93" to the credits to avoid blaming AT&T for our changes.
2020-06-18 11:52:32 +02:00
Martijn Dekker
8b51d12f4b data/builtins.c: cosmetic fix in comment 2020-06-18 03:40:29 +02:00
Martijn Dekker
3e3f6b0f12 Restore #22 'unset -f' fix minus segfault (re: b7932e87, 97511748)
Applying the fix for 'unset -f' exposed a crashing bug in lookup()
in sh/nvdisc.c, which is the function for looking up discipline
functions. This is what caused tests/variables.sh to crash.
Ref.: https://github.com/ksh93/ksh/issues/23#issuecomment-645699614

src/cmd/ksh93/sh/nvdisc.c: lookup():
- To avoid segfault, check that the function pointer nq->nvalue.rp
  is actually set before checking if nq->nvalue.rp->running==1.

src/cmd/ksh93/sh/xec.c,
src/cmd/ksh93/tests/functions.sh:
- Uncomment the 'unset -f' fix from b7932e87.

Resolves #21 (again).
2020-06-18 02:48:51 +02:00
Martijn Dekker
975117485c Part revert #22 to undo memory fault (re: b7932e87)
The fix in sh/xec.c, which was backported from the ksh 93v- beta to
delay the actual removal of a running function that unsets itself,
caused a segfault in the variables.sh regression tests (see #23).

src/cmd/ksh93/sh/xec.c:
- Comment out the backported code pending a correct fix for #21.
  Now both types of functions silently fail to unset themselves
  (unless they're discipline functions).

src/cmd/ksh93/tests/functions.sh:
- Disable regression tests checking that the function was actually
  unset, pending a correct fix for #21.

Resolves: #23
Reopens: #21
2020-06-17 21:01:55 +02:00
Johnothan King
b7932e87b6
Fix two problems with 'unset -f' behavior (#22)
src/cmd/ksh93/sh/name.c:
 - Correct the check for when a function is currently running
   to fix a segmentation fault that occurred when a POSIX
   function tries to unset itself while it is running.
   This bug fix was backported from ksh93v-.

src/cmd/ksh93/sh/xec.c:
 - If a function tries to unset itself, unset the function
   with '_nv_unset(np, NV_RDONLY)' to fix a silent failure.
   This fix was also backported from ksh93v-.

src/cmd/ksh93/tests/functions.sh:
 - Add four regression tests for when a function unsets itself.

Resolves #21
2020-06-17 18:26:43 +01:00
Martijn Dekker
746ce73671 regress: don't count temp dir creation as test (re: 2318de32)
Note that shtests simply does a 'grep -c err_exit' and substracts 1
to count the number of regression tests in a test script. Not all
test scripts make temp dirs, so subtracting 2 instead won't do.

src/cmd/ksh93/tests/*.sh:
- Escape the err_exit call in the routine to create a temporary
  directory so that it is not counted as a regression test.
  That bypasses the alias, so we have to pass $LINENO manually.
2020-06-17 17:14:03 +02:00
Martijn Dekker
9ff692c2bb regress: count tests and report line numbers (re: 7b994b6a)
Four added tests did not correctly report their line numbers
upon failure and were counted as one, because the err_exit
alias/function pair was called from a shell function.

Note that shtests simply does a 'grep -c err_exit' to count the
number of regression tests in a test script.

src/cmd/ksh93/tests/subshell.sh:
- check_hash_table():
  - Take line number as 1st argument.
  - Quote a character in err_exit to bypass the alias when calling
    it, so we can pass on the argument for the line number. This
    also stops this helper function from being counted as a test.
- When calling check_hash_table(), pass $LINENO.
- Add dummy err_exit comments to have the tests counted.
2020-06-17 16:07:09 +02:00
Johnothan King
fae8862c53
Fix assignments preceding 'command <special builtin>' (#19)
Ksh was not checking for `command` when running a special builtin,
which caused preceding invocation-local variable assignments to
become global. This is the reproducer from the att/ast#72:

$ foo=BUG command eval ':'
$ echo "$foo"

This no longer prints 'BUG', as ksh now makes sure the command builtin
is not running a special builtin before making invocation-local
variable assignments global.

src/cmd/ksh93/sh/xec.c:
 - Backport the bugfix for BUG_CMDSPASGN from ksh93v- 2013-10-10-alpha.

src/cmd/ksh93/tests/builtins.sh:
 - Add a regression test based on the reproducer in att/ast#72.
2020-06-16 22:58:05 +01:00
Johnothan King
c258a04f7a
Implement a portable fix for SIGCHLD crashes (#18)
As previously reported in rhbz#1112306 (https://bugzilla.redhat.com/show_bug.cgi?id=1112306),
ksh may crash when receiving SIGCHLD because GCC's optimizer will fail to generate
`addl` and `sub` instructions to increment and decrement `job.in_critical` in the
`job_subsave` function. This bug *does* occur in GCC 10 with `-O2`, but not `-O1`;
it doesn't appear this bug has been fixed. As a reference, here is the relevant
debug assembly output of `job_subsave` when KSH is compiled with `CCFLAGS` set to
`-g -O1`:

0000000000034c97 <job_subsave>:

void *job_subsave(void)
{
   34c97:       53                      push   %rbx
        struct back_save *bp = new_of(struct back_save,0);
   34c98:       bf 18 00 00 00          mov    $0x18,%edi
   34c9d:       e8 34 4a 0a 00          callq  d96d6 <_ast_malloc>
   34ca2:       48 89 c3                mov    %rax,%rbx
        job_lock();
   34ca5:       83 05 3c 50 13 00 01    addl   $0x1,0x13503c(%rip)        # 169ce8 <job+0x28>
        *bp = bck;
   34cac:       66 0f 6f 05 4c 5a 13    movdqa 0x135a4c(%rip),%xmm0        # 16a700 <bck>
   34cb3:       00
   34cb4:       0f 11 00                movups %xmm0,(%rax)
   34cb7:       48 8b 05 52 5a 13 00    mov    0x135a52(%rip),%rax        # 16a710 <bck+0x10>
   34cbe:       48 89 43 10             mov    %rax,0x10(%rbx)
        bp->prev = bck.prev;
   34cc2:       48 8b 05 47 5a 13 00    mov    0x135a47(%rip),%rax        # 16a710 <bck+0x10>
   34cc9:       48 89 43 10             mov    %rax,0x10(%rbx)
        bck.count = 0;
   34ccd:       c7 05 29 5a 13 00 00    movl   $0x0,0x135a29(%rip)        # 16a700 <bck>
   34cd4:       00 00 00
        bck.list = 0;
   34cd7:       48 c7 05 26 5a 13 00    movq   $0x0,0x135a26(%rip)        # 16a708 <bck+0x8>
   34cde:       00 00 00 00
        bck.prev = bp;
   34ce2:       48 89 1d 27 5a 13 00    mov    %rbx,0x135a27(%rip)        # 16a710 <bck+0x10>
        job_unlock();
   34ce9:       8b 05 f9 4f 13 00       mov    0x134ff9(%rip),%eax        # 169ce8 <job+0x28>
   34cef:       83 e8 01                sub    $0x1,%eax
   34cf2:       89 05 f0 4f 13 00       mov    %eax,0x134ff0(%rip)        # 169ce8 <job+0x28>
   34cf8:       75 2b                   jne    34d25 <job_subsave+0x8e>
   34cfa:       8b 3d ec 4f 13 00       mov    0x134fec(%rip),%edi        # 169cec <job+0x2c>
   34d00:       85 ff                   test   %edi,%edi
   34d02:       74 21                   je     34d25 <job_subsave+0x8e>
   34d04:       c7 05 da 4f 13 00 01    movl   $0x1,0x134fda(%rip)        # 169ce8 <job+0x28>

When `-O2` is used instead of `-O1`, the `addl` and `sub` instructions for
incrementing and decrementing the lock are removed. GCC instead generates a
broken `mov` instruction for `job_lock` and removes the initial `sub` instruction
in job_unlock (this is also seen in Red Hat's bug report):

       job_lock();
       *bp = bck;
  37d7c:       66 0f 6f 05 7c 79 14    movdqa 0x14797c(%rip),%xmm0        # 17f700 <bck>
  37d83:       00
       struct back_save *bp = new_of(struct back_save,0);
  37d84:       49 89 c4                mov    %rax,%r12
       job_lock();
  37d87:       8b 05 5b 6f 14 00       mov    0x146f5b(%rip),%eax        # 17ece8 <job+0x28>
...
        job_unlock();
  37dc6:       89 05 1c 6f 14 00       mov    %eax,0x146f1c(%rip)        # 17ece8 <job+0x28>
  37dcc:       85 c0                   test   %eax,%eax
  37dce:       75 2b                   jne    37dfb <job_subsave+0x8b>

The original patch works around this bug by using the legacy `__sync_fetch_and_add/sub`
GCC builtins. This forces GCC to generate instructions that change the lock with
`lock addl`, `lock xadd` and `lock subl`:

       job_lock();
  37d9f:       f0 83 05 41 6f 14 00    lock addl $0x1,0x146f41(%rip)        # 17ece8 <job+0x28>
  37da6:       01
...
       job_unlock();
  37deb:       f0 0f c1 05 f5 6e 14    lock xadd %eax,0x146ef5(%rip)        # 17ece8 <job+0x28>
  37df2:       00
  37df3:       83 f8 01                cmp    $0x1,%eax
  37df6:       74 08                   je     37e00 <job_subsave+0x70>
...
  37e25:       74 11                   je     37e38 <job_subsave+0xa8>
  37e27:       f0 83 2d b9 6e 14 00    lock subl $0x1,0x146eb9(%rip)        # 17ece8 <job+0x28>

While this does work, it isn't portable. This patch implements a different
workaround for this compiler bug. If `job_lock` is put at the beginning of
`job_subsave`, GCC will generate the required `addl` and `sub` instructions:

       job_lock();
  37d67:       83 05 7a 5f 14 00 01    addl   $0x1,0x145f7a(%rip)        # 17dce8 <job+0x28>
...
        job_unlock();
  37dbb:       83 e8 01                sub    $0x1,%eax
  37dbe:       89 05 24 5f 14 00       mov    %eax,0x145f24(%rip)        # 17dce8 <job+0x28>

It is odd that moving a single line of code fixes this problem, although
GCC _should_ have generated these instructions from the original code anyway.
I'll note that this isn't the only way to get these instructions to generate.
The problem also seems to go away when inserting almost anything else inside
of the code for `job_subsave`. This is just a simple workaround for a strange
compiler bug.
2020-06-16 22:44:02 +01:00
Johnothan King
764acefaf1 read -r -d should not ignore -r
This bug was previously reported in att/ast#37.
Ksh ignores `-r` when `read -r -d` is run because when
the bit for `D_FLAG` is set, the bit for `R_FLAG` is unset
as a side effect of setting `D_FLAG`. The following set
of commands fails to print a backslash:

$ printf '\\\000' | read -r -d ''
$ echo $REPLY

The fix for this bug is to set `D_FLAG` with `D_FLAG + 1`,
which prevents `R_FLAG` from being unset. This bugfix
has been backported from ksh93v- 2013-10-10-alpha.

src/cmd/ksh93/bltins/read.c:
 - Set `D_FLAG` with `D_FLAG + 1` to prevent the bit for
   `R_FLAG` from being unset.

src/cmd/ksh93/tests/builtins.sh:
 - Add the regression test for `read -r -d` from ksh93v-.
2020-06-16 13:49:23 +01:00
Martijn Dekker
ad349c7668 silence macro redefinition warnings (re: 7003aba4)
src/cmd/ksh93/bltins/test.c,
src/cmd/ksh93/sh/arith.c,
src/cmd/ksh93/sh/streval.c:
- #undef ERROR_exit before redefining it, so clang stops nagging.
2020-06-16 04:51:21 +02:00
Martijn Dekker
a9de50bf79 Apply simple optimisation for ${ subshare; } (re: 3d38270b)
Running shbench after undoing the incorrect subshell optimisation
showed that the performance of ${ subshare; }-type command
substitutions went down very slightly, but consistently.

The main purpose of using this ksh-specific type of command
substitution vs. a normal one is performance. Thus, it *is*
appropriate to eke every last bit of performance out of it that
we can, provided correctness is completely preserved.

It is also a type of command substitution where every change is
supposed to be shared with the main shell environment; only command
output is captured in a subshell-like fashion.

Thus, on the face of it, it would be a logical optimisation for
sh_assignok() to avoid bothering with saving a subshell context for
variables if we're in a subshare.

Lo and behold, applying it does not introduce any regress fails.

Here are my average results of the braces.ksh benchmark from
shbench <http://fossil.0branch.com/csb/tktnew> against stock
/bin/ksh 93u+ vs. current 93u+m (same compiler flags),
100 runs pre-optimisation and 100 runs post-optimisation:

Stock /bin/ksh:		Pre-optimisation (at 3d38270b):
93u+: 0.743 secs	93u+m: 0.739 secs

Stock /bin/ksh:		Post-optimisation (now):
93u+: 0.744 secs	93u+m: 0.726 secs

The left column shows only a small margin of error with 100 runs;
the right one shows a very small, but not insignificant difference.

However, these tests were not very rigorous with 100 runs each.
If anyone wants to do it properly, please report results to
korn-shell@googlegroups.com. I'm happy enough with this, though.

Thanks to Joerg van den Hoff for providing shbench, without
which it would not have occurred to me to try this.

src/cmd/ksh93/sh/subshell.c: sh_assignok():
- Don't bother if we're in a ${ subshare; }.
2020-06-15 20:27:32 +02:00
Martijn Dekker
6916a873c2 optget: display --help and --man in terse usage messages
The fact that every ksh builtin command self-documents with the
options --help and --man (and others, see 'getopts --man'; but
these are the essential ones) is poorly known; the information is
buried somewhere deep in the sh.1 manual page, and is incomplete at
that. None of the terse usage messages displayed on error point the
user to these options. So let's fix that.

src/lib/libast/misc/optget.c:
- Change generic 'options' placeholder, used in all terse usage
  messages, to 'options | --help | --man'.

src/cmd/ksh93/sh.1:
- Edit documentation of --man/-?, adding documentation on --help
  which was completely undocumented. Refer to 'getopts --man' for
  more advanced info.
- Separate these from the (important) documentation on special
  builtins using a paragraph break.
2020-06-15 16:56:11 +02:00
Martijn Dekker
7f2c81103b regress: avoid backporting a cmd subst bug from beta
ksh 93v- beta introduced a regression with nested command
substitutions: backticks nested in $( ) result in misdirected
output. This has never been in 93u+, but since we're often
backporting things, let's avoid backporting this bug. It is also
useful if this shows up when running our bin/shtests against the
actual beta by adding a SHELL=... argument.
Ref.: https://github.com/att/ast/issues/478

src/cmd/ksh93/tests/subshell.sh:
- Add reproducer submitted by the reporter as a regression test.
2020-06-15 16:52:12 +02:00
Johnothan King
3d38270b32 Remove a buggy optimization for variables in subshells
This bug was originally reported by @lijog in att/ast#7 and has been
reported again in #15. KSH does not save the state of a variable if it
is in a newer scope. This is because of an optimization in sh_assignok
first introduced in ksh93t+ 2010-05-24. Here is the code change in that
version:

                return(np);
        /* don't bother to save if in newer scope */
-       if(!(rp=shp->st.real_fun)  || !(dp=rp->sdict))
-               dp = sp->var;
-       if(np->nvenv && !nv_isattr(np,NV_MINIMAL|NV_EXPORT) && shp->last_root)
-               dp = shp->last_root;
-       if((mp=nv_search((char*)np,dp,HASH_BUCKET))!=np)
-       {
-               if(mp || !np->nvfun || np->nvfun->subshell>=sh.subshell)
-                       return(np);
-       }
+       if(sp->var!=shp->var_tree && shp->last_root==shp->var_tree)
+               return(np);
        if((ap=nv_arrayptr(np)) && (mp=nv_opensub(np)))
        {

This change was originally made to replace a buggier optimization.
However, the current optimization causes variables set in subshells
to wrongly affect the environment outside of the subshell, as the
variable does not get set back to its original value. This patch
simply removes the buggy optimization to fix this problem.

src/cmd/ksh93/sh/subshell.c:
 - Remove a buggy optimization that caused variables set in subshells
   to affect the environment outside of the subshell.

src/cmd/ksh93/tests/subshell.sh:
 - Add a regression test for setting variables in subshells. This
   test has to be run from the disk after being created with a here
   document because it always returns the expected result when run
   directly in the regression test script.
2020-06-15 07:13:38 -07:00
Martijn Dekker
ef1621c18f Make 'source' a regular built-in
The 'source' alias is now converted into a regular built-in command
so that 'unalias -a' does not remove it, and something like
	cmd=source; $cmd name args
will now work.

This is part of the project to replace default aliases that define
essential commands by proper builtins that act identically (except
you now get the actual command's name in any error/usage messages).

src/cmd/ksh93/data/aliases.c:
- Remove 'source' default alias.

src/cmd/ksh93/data/builtins.c,
src/cmd/ksh93/include/builtins.h:
- Define 'source' regular builtin with extra parser ID "SYSSOURCE".
  Same definition as '.', minus the BLT_SPC flag indicating a
  special builtin. This preserves the behaviour of 'command .'.
- Update sh_optdot[] to include info for 'source --man'.
  (Note that \f?\f expands to the current command name.
  This allows several commands to share a single --man page.)

src/cmd/ksh93/sh/parse.c:
- In the two places that SYSDOT is checked for, also check for
  SYSSOURCE, making sure the two commands are parsed identically.

src/cmd/ksh93/sh.1:
- Remove 'source' default alias.
- Document 'source' regular builtin.
2020-06-15 11:33:44 +02:00
Martijn Dekker
b7f48e8a10 Revert job locking patch (re: 07cc71b8, 58560db7)
This reverts the patch for the job_lock and job_unlock macros.

As I said in 58560db7, this is very probably a workaround for an
optimiser bug in certain versions of GCC, at least 2017 versions.

In the version I committed, that workaround version never gets
used, because you cannot use #if defined(...) to check for the
presence of a compiler builtin. Thanks to Johnothan King for
keeping an eye on my code and pointing that out to me.

What is needed to test for the presence of a compiler builtin is a
builtin macro called __has_builtin (and it *can* be tested for
using #if defined...()).. This is a clang invention. It was not
added to gcc until version 10, which was only released in a first
stable version just over a month ago.
Ref.: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66970#c14
      https://gcc.gnu.org/gcc-10/

However, for gcc 10, it seems unlikely the patch is still needed.
(Although it would certainly be a good idea to test that.)

And for the older gcc versions that do need it, we cannot use
__has_builtin, which means we need to define a dummy that always
returns false, so the workaround version is never used.
Ref.: https://github.com/ksh93/ksh/commit/58560db7#commitcomment-39900259

And we cannot use the workaround version unconditionally either,
because it would cause build failures on compilers without the
__sync_fetch_and_add() and __sync_fetch_and_sub() builtins.

Which means the only sensible thing left to do is to revert the
patch for now.

As far as I can tell at this point, for the patch to return to this
upstream in a sensible manner, someone would need to:

1. Write a small C program that tests these macros and somehow
   checks for the presence of that optimiser bug. (This is not
   going to come from me; my C-fu is simply not good enough.)

2. Incorporate that into the distribution as a test for iffe.
   (Few know how iffe works, but it's probably not that hard as
   there are plenty of existing tests to use as a template.)

3. Reinsert the workaround version using the macro defined (or not)
   by that iffe test, so that it is only compiled in when using a
   compiler that actually has the bug in question.

Until then, this can just continue to be an OS-specific patch for
systems with GCC versions that might have that bug.
2020-06-15 03:20:45 +02:00
Martijn Dekker
58560db768 Restore build without __sync_fetch_and_{add,sub} (re: 07cc71b8)
The more I think about it, the more it seems obvious that commit
07cc71b8 (PR #14) is quite simply a workaround for a GCC optimiser
bug, and (who knows?) possibly an old, long-fixed one, as the bug
report is years old.

The commit also caused ksh to fail to build on HP-UX B.11.11 with
GCC 4.2.3 (hosted at polarhome.com), because it doesn't have
__sync_fetch_and_add() and __sync_fetch_and_sub(). It may fail on
other systems. The GCC documentation says these are legacy:
https://gcc.gnu.org/onlinedocs/gcc/_005f_005fsync-Builtins.html

HELP WANTED: what I would like best is if someone could come up
with some way of detecting this optimiser bug and then error out
with a message along the lines of "please upgrade your broken
compiler". It would probably need to be a new iffe test.

Meanwhile, let's try it this way for a while and see what happens:

src/cmd/ksh93/include/jobs.h:
- Restore original ksh version of job_lock()/job_unlock() macros.
- Use the workaround version only if the compiler has the builtins
  __sync_fetch_and_add() and __sync_fetch_and_sub().
2020-06-14 23:49:07 +02:00
Martijn Dekker
f95d3105ef
Merge pull request #14 from aweeraman/debian-patches-2
ksh segfaults in job_chksave after receiving SIGCHLD

https://bugs.launchpad.net/ubuntu/+source/ksh/+bug/1697501
Eric Desrochers wrote on 2017-06-12:

[Impact]
* The compiler optimization dropped parts from the ksh job
  locking mechanism from the binary code. As a consequence, ksh
  could terminate unexpectedly with a segmentation fault after
  it received the SIGCHLD signal.

[Test Case]

Unfortunately, there is no clear and easy way to reproduce the
segfault.
* But the original reporter of this bug can randomly reproduce
  the problem using an in-house ksh script that only works
  inside his infrastructure as follow : "ksh
  <in-house-script.ksh>" and then once in a while ksh will
  segfault as follow :

(gdb) bt
#0 job_chksave (pid=pid@entry=19003) at /build/ksh-6IEHIC/ksh-93u+20120801/src/cmd/ksh93/sh/jobs.c:1948
#1 0x00000000004282ab in job_reap (sig=17) at /build/ksh-6IEHIC/ksh-93u+20120801/src/cmd/ksh93/sh/jobs.c:428
#2 <signal handler called>
...

[Regression Potential]
* Regression risk : low/none expected, the package has been
  highly/intensively tested by a user who run over 18M ksh
  scripts a day on each of their clusters.
[...]
* The fix has been written by RH and has been proven to work for
  them for the last 3 years.
* A test package including the RH fix has been intensively tested
  and verified (pre-SRU) by an affected user with positive
  feedbacks using a reproducer that segfault without the RH
  patch.
* Test package (pre-SRU) feedbacks :
  https://bugs.launchpad.net/ubuntu/xenial/+source/ksh/+bug/1697501/comments/7

[Other Info]
* Details about the RH bug :
  - https://bugzilla.redhat.com/show_bug.cgi?id=1123467
  - https://bugzilla.redhat.com/show_bug.cgi?id=1112306
  - https://access.redhat.com/solutions/1253243
  - http://rhn.redhat.com/errata/RHBA-2014-1015.html
  - ksh.spec
    * Fri Jul 25 2014 Michal Hlavinka <email address hidden> - 20120801-10.8
    * job locking mechanism did not survive compiler optimization (#1123467)
  - patch
    * ksh-20120801-locking.patch

Debian bug:
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=867181

[Original Description]

# gdb
[New LWP 3882]
Core was generated by `/bin/ksh <KSH_SCRIPT>.ksh'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 job_chksave (pid=pid@entry=19385) at /build/ksh-6IEHIC/ksh-93u+20120801/src/cmd/ksh93/sh/jobs.c:1948
1948 if(jp->pid==pid)

(gdb) p *jp
Cannot access memory at address 0xb

(gdb) p *jp->pid
Cannot access memory at address 0x13

(gdb) p pid
$2 = 19385

(gdb) p *jpold
$1 = {next = 0xb, pid = -604008960, exitval = 11124}

The struct is corrupted at some point looking at the next,pid and
exitval struct members values which isn't valid data.

# assembly code
=> 0x0000000000427159 <+41>: cmp %edi,0x8(%rdx)

(gdb) p $edi ## pid variable
$1 = 19385

(gdb) p *($rdx + 8) ## jp->pid struct
Cannot access memory at address 0x13
--

ksh is segfaulting because it can't access struct "jp" ($rdx)
thus cannot de-reference the struct member "jp>pid" ($rdx + 8) at
line : src/cmd/ksh93/sh/jobs.c:1948 when looking if jp->pid is
equal to pid ($edi) variable.
2020-06-14 21:46:32 +01:00
Anuradha Weeraman
07cc71b880 ksh segfaults in job_chksave after receiving SIGCHLD
Upstreaming Debian patch:

Prior to this update, the compiler optimization dropped parts from the ksh job
locking mechanism from the binary code. As a consequence, ksh could terminate
unexpectedly with a segmentation fault after it received the SIGCHLD signal.
This update implements a fix to ensure the compiler does not drop parts of the
ksh mechanism and the crash no longer occurs.

Author: Michal Hlavinka mhlavink@redhat.com
Origin: Red Hat fix, ksh-20120801-locking.patch
Bug: https://bugzilla.redhat.com/show_bug.cgi?id=1123467
Bug-Ubuntu: https://bugs.launchpad.net/bugs/1697501
Bug-Debian: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=867181
2020-06-14 16:19:33 -04:00
Martijn Dekker
ae25b7f886 move read -S regress test to readcsv.sh (re: af0bd6ad) 2020-06-14 20:10:22 +02:00
Johnothan King
af0bd6ad70 read -S now correctly handles nested double quotes
Prior to this bugfix, the following set of commands would
fail to print two double quotes:

IFS=',' read -S a b c <<<'foo,"""title"" data",bar'
echo $b

This fix is from ksh93v- 2013-10-10-alpha, although it has
been revised to use stakputc to put the required double quote
into the buffer for consistency with the ksh93u+ codebase.

src/cmd/ksh93/bltins/read.c:
 - When handling nested double quotes, put the required double
   quote in read's buffer with stakputc.

src/cmd/ksh93/tests/builtins.sh:
 - Add the regression test for `read -S` from ksh93v-.

src/cmd/ksh93/sh.1:
 - Fix a minor formatting error to highlight '-S' in the ksh(1)
   man page.
2020-06-14 10:40:30 -07:00
Martijn Dekker
5498d9ec25
Merge pull request #11 from JohnoKing/leap-seconds
Fix two more problems with time zones and epoch handling
2020-06-14 16:54:23 +01:00
Martijn Dekker
ff01ecdaba
Merge pull request #10 from aweeraman/debian-patches-1
Fixes for implicit declaration warnings

This is to upstream some minor fixes for implicit declaration warnings currently in Debian.

Author: Anuradha Weeraman aweeraman@gmail.com
Reviewed-By: Thorsten Glaser t.glaser@tarent.de
Last-Update: 2020-02-09
2020-06-14 16:43:37 +01:00
Martijn Dekker
a81a64060c sh.1: forgot update after d8eba9d1 2020-06-14 16:49:41 +02:00
Anuradha Weeraman
49cac9e604 Fixes for implicit declaration warnings
Signed-off-by: Anuradha Weeraman <aweeraman@gmail.com>
2020-06-14 09:55:08 -04:00
Johnothan King
51f97cf82f Fix two more problems with time zones and epoch handling
src/cmd/ksh93/edit/history.c:
 - The `time_t` data type is usually 64-bit, so cast `t` to an
   unsigned long and use the correct format specifier with sfprintf.

src/lib/libast/tm/tmdata.c:
 - Update the leap second array by adding the current leap
   seconds that were absent, being:

   2016-12-31+23:59:60  1483228826
   2015-06-30+23:59:60  1435708825
   2012-06-30+23:59:60  1341100824

   I couldn't find a proper list of leap seconds in Unix Epoch time,
   so I used an Epoch Converter:
   https://www.epochconverter.com/
   The converter doesn't support leap seconds, so each conversion
   had to be corrected by adding the number of leap seconds required
   (e.g. 1230767999 + 24 = 1230768023, for 2008-12-31+23:59:60 in GMT).
2020-06-14 06:53:46 -07:00
Martijn Dekker
6109f54a5e Fix for no-argument use of 'cd' in .../fun/dirs
'cd' with no argument is supposed to go to your home directory, but
in this override function it produced an error due to an incorrect
use of $@ within another parameter substitution, preventing $@ from
expanding to zero words.

Ref.: https://groups.google.com/d/msgid/korn-shell/781ed34b-6860-5d47-dfe8-be21280a6b31%40inlv.org

src/cmd/ksh93/fun/dirs: _cd():
- Fix the bug by setting a positional parameter if needed,
  then using a normal and correct "$@" expansion for \cd.
- While we're here, restore a historic comment about using
  'command' to bypass aliases that exists in the listing of this
  function in the official 1995 KornShell book (pp. 274-276).
  Presumably, that comment was deleted when they decided to add the
  obnoxious and broken default alias command='command ', whenever
  that was. This branch got rid of that default alias in 61d9bca5.
2020-06-14 10:39:48 +02:00
Martijn Dekker
d66f2a80d8 sh.1: default PS1 is "$ ", not "$" 2020-06-14 08:42:07 +02:00
Martijn Dekker
76f7d15a93
Merge pull request #8 from JohnoKing/fix-freebsd-date
Backport the ksh2020 fix for timezone name determination

Partial fix for #6.
2020-06-14 00:07:51 +01:00
Johnothan King
d7c9470704 Backport the ksh2020 fix for timezone name determination
This fix for `printf '%T' now` on FreeBSD was written by
@krader1961. This is from https://github.com/att/ast/pull/591:

On FreeBSD calling tzset() does not guarantee the tzname array will
be correctly populated. On most systems that works but on FreeBSD you
have to call localtime() or a related function (e.g., ctime()).

This change also eliminates a potential, very small, memory leak due to
the strdup()'ed tznames not being freed.

src/lib/libast/tm/tminit.c:
 - Fix timezone name determination on FreeBSD and a memory leak.
2020-06-13 14:28:10 -07:00
Johnothan King
7b994b6a7e Implement a better fix for unsetting special env vars
The regression this commit fixes was first introduced in ksh93t
2008-07-25. It was previously worked around in 6f0e008c by forking
subshells if any special environment variable is unset.

The reason why this problem doesn't occur in ksh93s+ is because in
that version of ksh sh_assignok never moves nodes, it only clones
them. The second argument doesn't set NV_MOVE, which makes
`sh_assignok(np,0)` is similar to `sh_assignok(np,1)`. In ksh93t and
higher, setting the second argument to zero causes the node to be moved
with NV_MOVE, which causes the discipline function associated with
the variable node to be removed when `np->nvfun` is set to zero (i.e.
NULL). This is why a command like `(unset LC_NUMERIC; LC_NUMERIC=invalid)`
doesn't print a diagnostic, as it looses its discipline function.

This patch fixes the problem by cloning the node with sh_assignok
if it is a special variable with a discipline function. This allows
special variables to work as expected in virtual subshells. The
original workaround has been kept for the $PATH variable only, as
hash tables are still broken in virtual subshells. It has been updated
accordingly to only fork subshells if it detects the variable node
for PATH. I have added two more regression tests for changing the
PATH in subshells to make sure hash tables continue working as
expected with this fix.

src/cmd/ksh93/bltins/typeset.c:
 - Only fork virtual subshells if the PATH will be changed. If a
   variable is a special variable with a discipline function, it
   should be just be cloned, not moved.

src/cmd/ksh93/sh/nvdisc.c:
 - Add a comment to clarify that NV_MOVE will delete the discipline
   function associated with the node.

src/cmd/ksh93/tests/subshells.sh:
 - Add two more regression tests for unsetting the PATH in subshells,
   one for if PATH is being pointed to by a nameref. Condense the
   hash table tests by moving the main test into a single function.
2020-06-13 12:55:48 -07:00
Martijn Dekker
289f56cd4c tests/pty.sh: fix regress fail due to $TMPDIR
Test 137(C) was failing on some systems because $TMPDIR was set and
the local vi(1) honours it, so that the expected '/tmp/' string was
never output by vi. For compatibility with vi programs that honour
$TMPDIR and those that always use /tmp, we must export TMPDIR=/tmp.

src/cmd/ksh93/tests/pty.sh:

- Export TMPDIR=/tmp for test 137(C).
     Note that this exports TMPDIR to the environment for the
  duration of the 'tst' function run because the function was
  defined using the ksh 'function tst { ...; }' syntax.
2020-06-13 01:48:13 +02:00
Martijn Dekker
d600cf61fa use 'ksh93' org identifier for new/changed builtins
We cannot identify the new builtins as coming from "AT&T Research"
as they don't. 'ksh community' is accurate but a bit long. Since
we're now at a GitHub org called ksh93, let's just use that.
2020-06-12 18:54:08 +02:00
Martijn Dekker
e500479ede
Merge pull request #1 from JohnoKing/fix-builtin-delete
`builtin -d` should not delete special builtins
2020-06-12 12:36:42 +01:00
Johnothan King
017d088c39 builtin -d should not delete special builtins
The man page for the builtin command says special builtins cannot
be deleted. This wasn't the case though, running `builtin -d` on
a special builtin was deleting it. As an example, the following
set of commands was ending with 'export: not found':

$ builtin -d export
$ export foo=bar

This commit backports the bugfix from ksh93v- (2014-12-24-beta),
which added an error check to prevent special builtins from being
deleted.

src/cmd/ksh93/sh/nvdisc.c:
 - Add an error check to prevent special builtins from being deleted.

src/cmd/ksh93/tests/builtins.sh
 - Add a regression test for using `builtin -d` on special builtins.
2020-06-12 04:26:40 -07:00
Martijn Dekker
cd5c181a39 Restore AST 'pty' pseudoterminal command (re: reboot)
This enables the tests/pty.sh regression tests for the interactive
shell to work. I've managed to restore these without restoring
nmake (which would cause unresolved build failures). It involved
hand-editing the Mamfile originally generated by nmake.

src/cmd/builtin/Makefile:
- Restored. Even though nmake is not installed, apparently mamake
  still needs the Makefile for the 'install' target to work. This
  will probably need editing if nmake is ever restored.

src/cmd/builtin/Mamfile:
- Restored and edited by hand to remove the commands to build all
  the utilities except pty, as well as all test targets (pty has no
  test). Most of this was systematically deleting blocks delimited
  by 'make FOO' and 'done FOO generated' until the build stopped
  failing -- a task made so much easier by the build now failing
  gracefully on error (see d0dfb37c). To see the diff, do:
	git diff cc1f2bf8 src/cmd/builtin/Mamfile

src/cmd/builtin/RELEASE:
- Restored for completeness' sake with all non-pty entries removed.

src/cmd/builtin/features/pty,
src/cmd/builtin/pty.c:
- Restored.
2020-06-12 12:35:58 +02:00
Martijn Dekker
802ea67afb tests/io.sh: don't abort entire suite on failure
src/cmd/ksh93/tests/io.sh:
- 16 tests for the 'redirect' builtin used the ((arithmetic
  command)) to check the result. This does not tolerate the result
  being a non-number, such as the empty string, which may occur on
  test failure. So use [[ ... -eq ArithExpression ]] to check these
  results instead; it simply returns false, failing gracefully.
2020-06-12 11:34:10 +02:00
Martijn Dekker
d8eba9d112 Remove 'login' and 'newgrp' builtins: not sane default behaviour
This commit removes the undocumented 'login' and 'newgrp' builtin
commands. They already stopped blocking shell functions by that
name by changing from special to regular builtins in 04b91718 (a
change I forgot to mention in that commit message), but there is
another obnoxious aspect to these: being glorified hooks into
'exec', they replaced your shell session with the external commands
by the same name. This makes argument and error checking
impossible, so if you made so much as a typo, you would be
immediately logged out.

Even if that behaviour is wanted by a few, having it as the default
is user-hostile enough to be called a bug. It also violates the
POSIX definition of the 'newgrp' utility which explicitly says that
it "shall create a new shell execution environment", not replace
the existing one.
https://pubs.opengroup.org/onlinepubs/9699919799/utilities/newgrp.html

Users who do want this behaviour can easily restore it by setting:
	alias login='exec login'
	alias newgrp='exec newgrp'

src/cmd/ksh93/bltins/misc.c:
- As there is no more 'login' builtin, combine b_exec() and
  B_login() functions, which allows eliminating a few variables.
  Note that most of 'exec' was actually implemented in B_login()!

src/cmd/ksh93/data/builtins.c:
- Remove "login" and "newgrp" table entries.

src/cmd/ksh93/include/builtins.h:
- Remove SYSLOGIN parser ID. As this was the first, all the others
  needed renumbering.

src/cmd/ksh93/sh/xec.c:
- Remove SYSLOGIN parser check that made 'login' and 'newgrp' act
  like 'exec' and replace the shell.
2020-06-12 06:57:57 +02:00
Martijn Dekker
7b82c338da Make 'redirect' a regular builtin instead of an alias of 'exec'
This commit converts the redirect='command exec' alias to a regular
'redirect' builtin command that only accepts I/O redirections, which
persist as in 'exec'. This means that:
* 'unlias -a' no longer removes the 'redirect' command;
* users no longer accidentally get logged out of their shells if
  they type something intuitive but wrong, like 'redirect ls >file'.

This should not introduce any legitimate change in behaviour. If
someone did accidentally pass non-redirection arguments to
'redirect', unexpected behaviour would occur; this now produces
an 'incorrect syntax' error.

src/cmd/ksh93/bltins/misc.c: b_exec():
- Recognise 'redirect' when parsing options.
- If invoked as 'redirect', produce error if there are arguments.

src/cmd/ksh93/data/aliases.c:
- Remove redirect='command exec' alias.

src/cmd/ksh93/data/builtins.c:
- Update/improve comments re ordering.
- Add 'redirect' builtin entry.
- sh_optexec[]: Abbreviate redirection-related documentation;
  refer to redirect(1) instead.
- sh_optredirect[]: Add documentation.

src/cmd/ksh93/include/builtins.h:
- Add SYSREDIR parser ID, renumbering those following it.
- Improve comments.
- Add extern sh_optredirect[].

src/cmd/ksh93/sh.1:
- exec: Abbreviate redirection-related documentation; refer to
  'redirect' instead.
- redirect: Add documentation.

src/cmd/ksh93/sh/xec.c:
- Recognise SYSREDIR parser ID in addition to SYSEXEC when
  determining whether to make redirections persistent.

src/cmd/ksh93/tests/io.sh:
- To regress-test the new builtin, change most 'command exec' uses
  to 'redirect'.
- Add tests verifying the exit behaviour of 'exec', 'command exec',
  'redirect' on redirections.
2020-06-12 04:54:33 +02:00
Martijn Dekker
936802f92a Simplify exit status fix, restore interruptability
The exit status fix introduced in cherry-picked commit 22c3a6e1
introduced a problem: interrupting the build only interrupted the
main process, and the background job would happily continue.

bin/package, src/cmd/INIT/package.sh:
- Give up on the idea of a background job and put up with not
  cleaning up the FIFO. It's in a build directory that is going to
  get cleaned up anyway.
2020-06-12 02:11:46 +02:00
Martijn Dekker
7a8a46700c Build on more darwin/macOS versions
src/cmd/INIT/cc.darwin*:
- Build on ancient Mac OS X gcc versions (darwin 7+, Mac OS X
  10.3+), more recent gcc versions (darwin 11+, Mac OS X 10.7+), as
  well as current clang versions. So there are now three cc.darwin*
  wrapper scripts for these different darwin versions.

bin/package, src/cmd/INIT/package.sh:
- Differentiate the host ID and pick the correct Darwin script based on
  the detected OS release version.
2020-06-12 01:45:19 +02:00
Martijn Dekker
04b9171858 POSIX compliance fix: make 'unalias' a regular builtin
Both 'alias' and 'unalias' are specified as regular builtins. Among
a few other things, that means it ought to be portable to use these
names for shell functions. But ksh93 disallowed that until now.

src/cmd/ksh93/data/builtins.c:
- Make 'unalias' a regular builtin by removing the BLT_SPC flag.
- (same fix for 'alias' was already done in afa68dca)
- Add the BLT_ENV flag to the 'alias' and 'hash' commands. In
  include/name.h, this flag is commented: "non-stoppable, can
  modify environment". The "non-stoppable" bit seems like a good
  idea: these operations should not be interruptable as that would
  cause an inconsistent state.

src/cmd/ksh93/sh.1:
- Remove the '-', indicating special builtin, from 'alias' entry.
- Minor cosmetic fix: space after the '-' for 'unset'.

(cherry picked from commit a4315d7672204acb543010b4d4916b22dcb9cb08)
2020-06-12 01:45:18 +02:00
Martijn Dekker
2da22f4023 data/builtins.c: minor cosmetic 'alias --man' fix (re: d8428a833)
(cherry picked from commit 98be5130d3a46a565d0ad601aac838531765fc43)
2020-06-12 01:45:18 +02:00
Martijn Dekker
80d9ae2b1c Refactor new b_hash(); better hash table clear (re: d8428a83)
The b_hash() function duplicated much of its code from b_alias(),
while b_alias() retained some code to support being called as
'hash'. There is no reason why 'hash' and 'alias' can't be handled
with a single function, as is the case several other builtins. Note
that option parsing can easily be made dependent on the name the
command was invoked with (in this case, argv[0]=='h').

The new hash builtin's -r option cleared the hash table by
assigning to PATH its existing value, triggering its associated
discipline function (put_restricted() in init.c) which then
actually cleared the hash table. That's a bit of a hack. It's nicer
if we can just do that directly. This requires taking a static
handler function rehash() from init.c, which invalidates one hash
table entry, and making it available to the builtin.

src/cmd/ksh93/bltins/typeset.c,
src/cmd/ksh93/include/builtins.h,
src/cmd/ksh93/include/nval.h,
src/cmd/ksh93/sh/init.c,
src/cmd/ksh93/sh/name.c:
- Merge b_hash() into b_alias().
- The -x option was still uselessly setting the NV_EXPORT flag.
  Exported aliases were in ksh88 but were removed in ksh93.
- Rename rehash() handler function from init.c to nv_rehash
  (avoiding a possible conflict with another rehash() in cd_pwd.c)
  and move it to name.c just above nv_scan(), which it's meant to
  be used with. Make it an extern so typeset.c can use it.
- b_alias(): Replace the PATH assignment by an nv_scan() call to
  clear the hash table directly using the nv_rehash() handler.

src/cmd/ksh93/data/builtins.c:
- POSIX compliance fix: Remove BLT_SPC (special builtin) flag from
  "alias" definition. 'alias' is specified as a regular builtin.
- sh_optalias[]: Fix uninformative -t option documentation.
- sh_opthash[]: Edit for conciseness and clarity.

src/cmd/ksh93/sh.1:
- Edit the 'alias -t' and 'hash' documentation.
- Remove the -- prefix from the 'alias' entry, which indicated that
  it was supposed to be a declaration builtin like 'typeset', with
  assignment-arguments expanding tildes and not being subject to
  field splitting. However, my testing shows that 'alias' has never
  actually behaved that way on ksh93. Even adding the BLT_DCL flag
  in data/builtins.c doesn't seem to change that.

(cherry picked from commit afa68dca5c786daa13213973e8b0f9bf3a1dadf6)
2020-06-12 01:45:18 +02:00
Johnothan King
74b4162178 Fix set +r so that it cannot unset the restricted option
The ksh man page documents that the restricted option cannot be
unset once it is set, which means `set +r` should be invalid.
While this was true for `set +o restricted`, `set +r` was causing
the restricted option to be unset. The fix for this problem comes
from one of Solaris' patches, which adds an error check to prevent
this behavior.

Solaris' patch:
https://github.com/oracle/solaris-userland/blob/master/components/ksh93/patches/020-CR6919590.patch

src/cmd/ksh93/sh/args.c:
 - Add an error check to stop `set +r` from unsetting the
   restricted option.

src/cmd/ksh93/tests/restricted.sh:
 - Add two regression tests to make sure the restricted option
   cannot be unset.

(cherry picked from commit bef4fee404d8e24b38fce66420c14a39ac4a123e)
2020-06-12 01:45:18 +02:00
Martijn Dekker
9cef2d534a shtests: make tests more interruptable with Ctrl+C
Sometimes you have to put ^C on rapid repeat to get out of running
the tests. This is because each test scripts is launch as a child
shell (not a subshell) in the foreground, which thus handle the ^C.
It then exits with a status indicating SIGINT, but the shtest script
wasn't handling this and just kept going.

src/cmd/ksh93/tests/shtests:
- For reasons I don't understand yet, interrupting tests with ^C
  tends to make them exit with status 130 (128+2) instead of what
  I would expect for ksh93, 258 (256+2). Not a big deal: POSIX
  specifies that any exit > 128 signifies a signal in any case,
  and 'kill -l' works even on those values. But the checks need
  changing to '> 128'.
- Check each result for SIGINT, and issue SIGINT to self if found.

(cherry picked from commit d0dfb37c6c71ac7b157060249125e0959130927d)
2020-06-12 01:45:18 +02:00
Johnothan King
102868f850 Replace the hash alias with a proper builtin
This commit replaces the old hash alias with a proper builtin.
I based this builtin off of the code alias uses for handling
`alias -t --`, but with the hack for `--` removed as it has
no use in the new builtin. `alias -t --` will no longer work,
that hack is now gone.

While I was testing this builtin, I found a bug with hash tables
in non-forking subshells. If the hash table of a non-forking
subshell is changed, the parent shell's hash table is also changed.
As an example, running `(hash -r)` was resetting the parent shell's
hash table. The workaround is to force the subshell to fork if the
hash table will be changed.

src/cmd/ksh93/bltins/typeset.c:
 - Move the code for hash out of the alias builtin into a dedicated
   hash builtin. `alias -t --` is no longer supported.

src/cmd/ksh93/data/aliases.c:
 - Remove the old alias for hash from the table of predefined aliases.

src/cmd/ksh93/data/builtins.c:
 - Fix the broken entry for the hash builtin and add a man page for
   the new builtin.

src/cmd/ksh93/sh.1:
 - Replace the entry for the hash alias with a more detailed entry
   for the hash builtin.

src/cmd/ksh93/sh/name.c:
 - Force non-forking subshells to fork if the PATH is being reset
   to workaround a bug with the hash tree.

src/cmd/ksh93/tests/alias.sh:
 - Add a regression test for resetting a hash table, then adding
   a utility to the refreshed hash table.

src/cmd/ksh93/tests/subshell.sh:
 - Add regression tests for changing the hash table in subshells.

(cherry picked from commit d8428a833afe9270b61745ba3d6df355fe1d5499)
2020-06-12 01:45:18 +02:00
Martijn Dekker
d1bd8f89b7 shtests: print CPU times used at end (re: ebf71e61)
Since we now have a shiny new POSIX compliant 'times' builtin,
we might as well use it.

src/cmd/ksh93/tests/shtests:
- Run 'times' at end of test run.
- Skip the pretty-printing until #7 is fixed.

(cherry picked from commit 2c27d9fbc239583004ec70377db98627eea5e294)
2020-06-12 01:45:18 +02:00
Johnothan King
e92faddbf9 Fix 39 spelling errors and a formatting issue
A column of whitespace in the NEWS file was removed for consistent
formatting. Most of the spelling errors were found with this
codespell dictionary:
https://github.com/orbitcowboy/codespell_dictionary

(cherry picked from commit 0e36b17abe5609c461a3e4da7041eb0fdf9991b7)
2020-06-12 01:45:18 +02:00
Martijn Dekker
90fd867171 Update manual after a0e0e29e
An oversight...

src/cmd/ksh93/sh.1:
- Undocument the fixed ${.sh.subshell} breakage.

(cherry picked from commit 42be8a3c6dd5a76d03e0456d7f53e38536757aa5)
2020-06-12 01:45:18 +02:00
Martijn Dekker
a1f46d785f rm "I/O error" error msg; just keep >0 exit status (re: 9011fa93)
The bug was really that I/O errors in output builtins were
undetectable by any means. Having a >0 exit status is sufficient.
Adding an error message risks making existing ksh scripts noisier,
or even breaking them if they redirect stderr to stdout.

Note to self: in future, implement the minimum change necessary to
fix bugs, nothing more. The fact that I needed to add four extra
2>/dev/null to the regression tests should have been a hint.

src/cmd/ksh93/bltins/print.c,
src/cmd/ksh93/data/msg.c,
src/cmd/ksh93/include/io.h:
- Remove "I/O error" message.

src/cmd/ksh93/tests/builtins.sh:
- Update to check for exit status only.

src/cmd/ksh93/tests/basic.sh,
src/cmd/ksh93/tests/coprocess.sh:
- Revert four new '2>/dev/null' to suppress the error message.

(cherry picked from commit 5e17be24d18455b575b6e98bc631c6935ffc795a)
2020-06-12 01:45:18 +02:00
Martijn Dekker
b883c7a7f8 remove extra 'isalias' variable (re: 16d5ea9b)
src/cmd/ksh93/bltins/typeset.c: unall():
- There's no need to keep track of whether we're unsetting an alias
  using a new 'isalias' vaariable, as we can just repeat the check
  for 'troot==shp->alias_tree'.

(cherry picked from commit 68f3ae3acd0d19dd80805049a1c9afc1ae1e75c3)
2020-06-12 01:45:18 +02:00
Johnothan King
5d50f825e4 The unalias builtin should return an error for non-existent aliases
This commit fixes a bug that caused unalias to return a zero status
when it tries to remove an alias twice. The following set of commands
will no longer end with an error:

$ alias foo=bar
$ unalias foo
$ unalias foo && echo 'Error'

This commit is based on the fix present in ksh2020, but it has been
extended with another bugfix. The initial fix for this problem tried to
remove aliases from the alias tree without accounting for NV_NOFREE. This
caused any attempt to remove a predefined aliases (e.g. `unalias float`)
to trigger an error with free, as all predefined aliases are in read-only
memory. The fix for this problem is to set NV_NOFREE when removing aliases
from the alias tree, but only if the alias is in read-only memory. All
other aliases must be freed from memory to prevent memory leaks.

I'll also note that I am using an `isalias` variable rather than the `type`
enum from ksh2020, as the `VARIABLE` value is never used and was replaced
with a bool called `aliases` in the ksh2020 release. The `isalias` variable
is an int as the ksh93u+ codebase does not use C99 bools.

Previous discussion: https://github.com/att/ast/issues/909

- src/cmd/ksh93/bltins/typeset.c:
  Remove aliases from the alias tree by using nv_delete. NV_NOFREE
  is only used when it is necessary.

- src/cmd/ksh93/tests/alias.sh:
  Add two regression tests for the bugs fixed by this commit.

(cherry picked from commit 16d5ea9b52ba51f9d1bca115ce8f4f18e97abbc4)
2020-06-12 01:45:18 +02:00
Martijn Dekker
d18469d608 bin/package: exit with nonzero status on build failure
Build scripts and the like ought to be able to check the results of
the build using the exit status of the build command.

bin/package,
src/cmd/INIT/package.sh:
- Add global error_status variable to keep track of the highest
  exit status of all commands using capture(). Exit with that.
- capture():
  * When capturing build output using 'tee', change the regular
    pipe construct (which doesn't preserve the exit status of pipe
    elements except the last one) to a couple of background jobs
    connected with a FIFO (named pipe). This allows getting the
    build's exit status using the "wait" command.
  * Update error_status on every invocation of capture().

(cherry picked from commit 22c3a6e1b32f3ab7eeca45adb76863982dc3e334)
2020-06-12 01:45:17 +02:00
Johnothan King
22d6b4527d Avoid brute-forcing during the build process to prevent failed builds
The default behavior of the package script is to ignore
errors. This has disastrous effects if any part of ksh
or libast fails to build due to something like a syntax
error, as the build will stop long after the first error
occurred.

This commit removes the -k flag from the $makeflags variable
in both copies of the package script. This forces the build
to fail if a compiler error occurs.

bin/package and src/cmd/INIT/package.sh:
 - Remove the -k assignment to $makeflags so that compiler
   errors cause the build to fail.

(cherry picked from commit 87bfaa19f3d336feb7b7bd4f5d4caf8d553f2547)
2020-06-12 01:45:17 +02:00
Martijn Dekker
c2eabc57e0 shtests: report total errors on terminal and in exit status
Setting the exit status allows build scripts and the like
to actually detect regression test failures.

src/cmd/ksh93/tests/shtests:
- Add counter for total number of errors.
- Report total to stdout at the end.
- Set the exit status to the total number of errors, up to 125
  (higher statuses have special meanings).

(cherry picked from commit c0dd80b14d4d316b4e9eff4b1b67d4e47f23a6ba)
2020-06-12 01:45:17 +02:00
Martijn Dekker
fb652a7e50 shtests: fix loose ends
src/cmd/ksh93/tests/variables.sh:
- Tolerate a bit more time for the SECONDS verification test.

src/cmd/ksh93/tests/subshell.sh:
- Replace unportable 'head -c 1' by 'dd bs=1 count=1'
- Remove unnecessary uses of 'whence'.

src/cmd/ksh93/tests/builtins.sh:
- Add a regression test for a weirdly specific 'whence' bug exposed
  by the aforementioned unneccessary uses of 'whence', which only
  shows up on my old Power Mac G5 running Mac OS X 10.3. For all I
  know it's a compiler bug, but let's add a more clear failure for
  it here, in case that happens anywhere else.

(cherry picked from commit c3898bd1e6e40874845771d33a5b37220ef0b06e)
2020-06-12 01:45:17 +02:00
Martijn Dekker
712261c89b shtests: More speedups; also fix xtrace (re: 734e5953)
This reduces a bunch more unnecessarily long sleeps to give
asynchronous processes time to run, etc. (No, we don't need to be
compatible anymore with your cool 1985 Intel 80386DX 16 MHz
battlestation...) Running the test suite is almost tolerable now,
making me much more likely to actually run the regression test
suite and catch my own regressions.

In addition, there are various fixes to make the test suite
compatible with 'set -x' ('set -o xtrace') so that you can now
actually *use* the documented 'bin/shtests -x' option. Recommend
combining with '-p' to avoid tracing everything three times.

I've also added a really useful $PS4 trace prompt to shtests that
traces pretty much everything there is to trace. (It does use
expansions that modify ${.sh.match}, which affected several tests,
particularly in tests/substring.sh; for those we need to set a
temporary simpler $PS4.)

(cherry picked from commit c3a5d47cfe880b526cabb5370ddaced0e8626acd)
2020-06-12 01:45:17 +02:00
Johnothan King
ba1f2ba9c3 Fix a build error on Linux due to wrong include ordering
This regression was caused by the commit that introduced
the times builtin. The ordering of the #include directives
was causing the build to fail on Ubuntu 20.04 and Arch Linux.

src/cmd/ksh93/bltins/misc.c:
 - Move the includes for standard headers to the bottom
   of the includes to fix build failures on Linux.

(cherry picked from commit 3a42b206a0cc71bedc4773ce545435570e862e61)
2020-06-12 01:45:17 +02:00
Martijn Dekker
40d0bdc287 Fix regression in 'return' introduced by 98e0fc94
This fixes two regression test failures in tests/functions.sh.

src/cmd/ksh93/bltins/cflow.c: b_exit():
- The exit status should of course only be cropped to 8 bits if
  b_exit() will actually exit, not if it returns from a function.

(cherry picked from commit 2d1e7f87551159c942b16de2a98dc72697988d26)
2020-06-12 01:45:17 +02:00
Johnothan King
b5e52703e9 Fix an issue with the up arrow key in Emacs editing mode.
Emacs editing mode is bugged in ksh93u+ and ksh2020. Let's
say you were to run the following commands after starting
a fresh instance of ksh:

$ alias foo='true'
$ unalias foo

If you type 'a' and then press the up arrow on your keyboard,
ksh will complete 'a' to `alias foo='true'` by doing a reverse
search for the last command that starts with 'a'.
Run the alias command again, then type 'u' and press the up
arrow key again. If ksh is in Vi mode, you will get `unalias foo`,
but in Emacs mode you will get `alias foo='true'` again.

This bug was occurring because ksh was only doing a reverse search
based on the first command that was completed using the up arrow.
All subsequent commands were ignored as ksh was saving the first
command and only based later searches off of it.

NEWS:
 - Add instructions for reproducing this bug with the up arrow
   key and information about why this bug was happening in the
   first place.

src/cmd/ksh93/edit/emacs.c:
 - Remove a bad check that was preventing ksh from using the
   latest input for reverse search.

(cherry picked from commit 745b065487ad6bac693ec6f44752f96e87f9a63b)
2020-06-12 01:45:17 +02:00
Martijn Dekker
8f90d98280 tests/signal.sh: slash sleeps by 10 to reduce a long wait
The signal.sh regression tests took over a minute and a half to
complete, so with the default three runs (for different locales)
they took about five minutes. Annoying and unnecessary. As ksh
supports floating point shell arithmetic plus a 'sleep' builtin
that supports fractional seconds, this is easy to fix.

src/cmd/ksh93/tests/signal.sh:
- Slash all the 'sleep' arguments and associated factors by a
  factor of 10. Since computers are now hundreds or thousands of
  times faster than they were in the early 1990s, this should be
  plenty safe enough and all the tests should still be valid.
- Change one unportable direct invocation of /bin/sleep to use the
  builtin.

(cherry picked from commit 734e5953650e9a62048c45eb9a3b827bb9efcfb5)
2020-06-12 01:45:17 +02:00
Martijn Dekker
d024d4c895 Fix signal handling due to exit status > 256
This fixes two bugs: issuing the 'exit' command with a value > 256
would cause ksh 93u+ to kill itself with the corresponding signal
(try 'exit 265' to SIGKILL your interactive shell), and, if the
last command of a script exits due to a signal, the shell would
repeat that signal to itself, causing any parent ksh to also be
killed.

Discussion:
https://bugzilla.redhat.com/show_bug.cgi?id=1469624
https://rainbow.chard.org/2017/03/21/ksh-deliberately-segfaults-if-the-last-command-in-a-script-crashes/

This commit is loosely based on a patch applied to the 93v- beta
and the abandoned ksh2020, but that patch was incomplete & broken:
  $ ksh-2020.0.0 -c 'exit 265'; echo $?
  137
Expected: 9. Since the exit was *not* due to a signal, the value
should simply be cropped to the 8 bits supported by the OS.

src/cmd/ksh93/bltins/cflow.c: b_exit():
- For the 'exit' builtin command, bitwise-AND the argument to
  'exit' with SH_EXITMASK (8 bits, crop to 0-255) before passing it
  on to sh_exit(). This restores the behaviour of <=2011 ksh93
  versions and is in line with all other POSIX shells.
  It also fixes this bogosity:
    $ (exit 265); echo $?                   # non-forked subshell
    265
    $ (ulimit -t unlimited; exit 265); echo $?  # forked subshell
    9
  Forked or non-forked should make no difference at all
  (see commit message a0e0e29e for why).

src/cmd/ksh93/sh/fault.c: sh_done():
- If the current exit status is equal to the status for the last
  signal that was received from a child process, remove the
  SH_EXITSIG (9th) bit, so that the shell doesn't kill itself.
- If the shell's last child process exits due to a signal, exit
  with a portable 8-bit exit status (128 + signal number). This
  avoids the exit status being < 128 by being cropped to 8 bits.

src/cmd/ksh93/tests/signal.sh:
- Add regression test for exit with status > 256.
- Add regression test verifying the shell no longer kills itself.

(cherry picked from commit 98e0fc94393e175ce6adfee390327c320795bf12)
2020-06-12 01:45:17 +02:00
Martijn Dekker
f88f302c38 Remove code related to long-dead 3DFS research project
This commit gets rid of dead weight related to an obscure early
1990s Bell Labs versioning file system research project called
3DFS, which has not existed for decades and for which I have not
managed to find any evidence that it was ever used outside the lab.

This removes:
- the SHOPT_FS_3D compile option (which was forced on even when 0)
- the obnoxious default alias 2d='set -f;_2d' that turned off your
  globbing and then tried to run a nonexistent _2d command
- undocumented builtins 'vmap' and 'vpath' that only errored out
- a non-functional -V unary operator for the test and [[ commands
- some specific code for Apollo workstations (last made in 1997),
  which was inseparably intertwined with the 3DFS code

(cherry picked from commit 20cdf3709f4fb4e468057b534dcee819b1961fb6)
2020-06-12 01:45:17 +02:00
Martijn Dekker
5f8b0512f0 POSIX compliance fix: apply 'set -u' to $!
POSIX requires[*] that expanding any unset parameter other than $@
and $* is an error when 'set -u'/'set -o nounset' is active.
However, on ksh93, $! was exempt as well. That is a bug.
[*] https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_25

src/cmd/ksh93/sh/macro.c:
- special(): Handle 'set -u' for special parameters if/when it is
  about to return NIL. That code path is currently only possible to
  reach for "$!", but this is future-proof and will do the right
  thing if any other special parameter can ever have no value.

src/cmd/ksh93/tests/options.sh:
- Add and tweak 'set -u' regression tests.

(cherry picked from commit 75cc7a38cafe3a9929e1ed17d8b952babda22a09)
2020-06-12 01:45:17 +02:00
Martijn Dekker
36da314c9e POSIX compliance fix: apply 'set -u' to $1, $2, ...
POSIX requires[*] that expanding any unset parameter other than $@
and $* is an error when 'set -u'/'set -o nounset' is active.
However, on ksh93, $1, $2, ... were exempt as well. That is a bug.
[*] https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_25

src/cmd/ksh93/sh/macro.c:
- varsub(): Backport code for handling 'set -u' for positional
  parameters from the ast 2016-10-01-beta branch.

src/cmd/ksh93/tests/options.sh:
- Add relevant regression tests.

src/cmd/ksh93/sh.1:
- Document that $@ and $* are exempt from 'set -u'.

(cherry picked from commit f954c6be0748c4c38a680a75f27564965fbd328e)
2020-06-12 01:45:17 +02:00
Martijn Dekker
e2a648b41f tests/options.sh: fix child shell test by exporting variable
src/cmd/ksh93/tests/options.sh:
- Pipe hang bugfix test: The child shell has no idea how long to
  sleep for if we don't export the variable telling it so.

(cherry picked from commit ede0960c4ec84f0f934b17072a892a4e40798e97)
2020-06-12 01:45:17 +02:00
Martijn Dekker
781f0a39aa Fix parsing of multibyte characters
According to Red Hat, this fixes "a bug on input buffer boundary
and/or temporary composing buffer of multibyte characters".
The patch was credited to Paulo Andrade <pandrade@redhat.com>.

To be honest, I don't know how to trigger this bug or what the code
removed by this fix really does, but this patch is in production
use at Red Hat, removes some smelly stuff, and is not triggering
any regression test failures, so I'll just take this one on faith.

https://bugzilla.redhat.com/show_bug.cgi?id=1417886
https://github.com/att/ast/commit/4fa2020b

src/cmd/ksh93/sh/fcin.c:
- _fcmbget(): Remove some dodgy-looking buffer-fiddling code that
  is marked as "for testing purposes with small buffers".

(cherry picked from commit 407760fdbddcb7f8ac92b5d1da29d3e09dac0369)
2020-06-12 01:45:17 +02:00
Martijn Dekker
7559f83eff Fix ksh hanging in pipes
Under certain conditions, ksh scripts may hang when piped through
a program that terminates before EOF.

Discussion and reproducer:
https://bugzilla.redhat.com/show_bug.cgi?id=1457990
https://www.mail-archive.com/ast-developers@lists.research.att.com/msg01961.html

src/cmd/ksh93/sh/jobs.c:
- In job_wait(), correctly set the terminal foreground process
  group when resuming a process.

(cherry picked from commit 99ef2ca5309da91fdead74bea00743960d470c6a)
2020-06-12 01:45:16 +02:00
Martijn Dekker
98c1e37d86 Fix memory corruption while parsing functions
Discussion: https://bugzilla.redhat.com/show_bug.cgi?id=1451057

src/cmd/ksh93/sh/parse.c: funct():
- Make the savstak variable volatile and always initialise it to
  avoid undefined behaviour.

(cherry picked from commit 5e56b28cd63ec2120c5f70a6e0abf2f8dbb7e7dc)
2020-06-12 01:45:16 +02:00
Martijn Dekker
b9f28bc508 cleanup: remove pointless no-op 'fc' and 'type' aliases
Both 'fc' and 'type' are already implemented as perfectly
functional builtins -- in fact they use the exact same C function
as 'hist' and 'whence', so the behaviour is clearly identical.

Except 'type' was aliased to 'whence -v', but b_whence() contains
explicit code to activate the v flag if invoked as 'type', so the
alias is not needed for that either.

It looks like someone decided to implement these aliases as proper
builtins (as they should be; they are POSIX standard commands and
'unalias -a' must not get rid of them), but then forgot to remove
these default aliases (and to update the man page).

I'm not even doing a NEWS entry for this as there is no change in
behaviour. The only difference is that you now get the correct
command name in error and usage messages for 'fc' and 'type'.

src/cmd/ksh93/data/aliases.c:
- Remove fc='hist' and type='whence -v' default aliases.

src/cmd/ksh93/sh.1:
- Remove those default aliases from the list.
- Document 'fc' and 'type' builtins.

(cherry picked from commit c73af6a5a36a72c681201c9e9c397f98bbf2a86d)
2020-06-12 01:45:16 +02:00
Martijn Dekker
61d9bca581 POSIX compliance: rm harmful default aliases 'command '/'nohup '
Continuing alias substitution after 'command' (due to the final
space in the alias) is inherently broken and doing so by default is
incompatible with the POSIX standard, as aliases may contain
arbitrary shell grammar.

For instance, until the previous commit, the POSIX standard 'times'
command was an alias: times='{ { time;} 2>&1;}' -- and so, of
course, 'command times' gave a syntax error, although this is
a perfectly valid POSIX idiom that must be supported.

'command' is specified by POSIX as a regular builtin, not an alias.
Therefore it should always bypass aliases just as it bypasses
functions to expose standard builtin and external commands.

I can only imagine that the reason for this command='command '
alias was that some standard commands themselves were implemented
as aliases, and POSIX requires that standard commands are
accessible with the 'command' prefix. But implementing standard
commands as aliases is itself inherently broken. It never worked
for 'command times', as shown; and in any case, removing all
aliases with 'unalias -a' should not get rid of standard commands.

Similarly, the default alias nohup='nohup ' is also harmful.

Anyone who really wants to keep this behaviour can just define
these aliases themselves in their script or ~/.kshrc file.

src/cmd/ksh93/data/aliases.c:
- Remove default alias command='command '.
- Remove default alias nohup='nohup '.

src/cmd/ksh93/sh.1
- Remove the above default aliases from the list.
- Mention that the 'command' builtin does not search for aliases.

(cherry picked from commit 5cfe7c4e2015b7445da24983af5008035c4b6e1e)
2020-06-12 01:45:16 +02:00
Martijn Dekker
65d363fd34 POSIX compliance fix: make 'times' a proper builtin
As of this commit, the 'times' command is a POSIX-compliant special
builtin command instead of an alias that doesn't produce the
required output. It displays the accumulated user and system CPU
times, one line with the times used by the shell and another with
those used by all of the shell's child processes.
https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_27

This was originally written by Kurtis Rader and is now backported
and tweaked from the abandoned ksh2020 branch. I chose an earlier
and simpler version[*1] that uses times(3), with a precision of
hundredths of seconds, so it outputs the same precision as mksh and
zsh. Rader later wrote another version[*2] that uses getrusage(2),
giving it the same millisecond precision as bash. But that required
adding a feature test and a fallback to the old version, which is
non-trivial in the old INIT/iffe system. This simpler version is
enough to gain POSIX compliance and I think it will do very nicely
in this stable bugfix branch.

[*1] https://github.com/att/ast/pull/1332
[*2] https://github.com/att/ast/commit/038045f6

src/cmd/ksh93/bltins/misc.c
- Add b_times() function for 'times' builtin.
- Note we include <times.h>, not <sys/times.h>, so that we use the
  AST feature-tested version with fallback on systems that need it.

src/cmd/ksh93/data/aliases.c:
- Remove times='{ { time;} 2>&1;}' builtin alias.

src/cmd/ksh93/data/builtins.c,
src/cmd/ksh93/include/builtins.h:
- Add entry for 'times' special builtin.
- Add --help/--man info for same.

src/cmd/ksh93/sh.1:
- Update manual page.

src/cmd/ksh93/tests/builtins.sh:
- Add a couple of simple regression tests.

(cherry picked from commit ebf71e619eb298ec1cf6b81d1828fa7cdf6e9203)
2020-06-12 01:45:16 +02:00
Martijn Dekker
3a3776f1df INIT/cc.darwin: re-suppress redefined macro warnings (re: a1d8ff6f)
Allowing redefined macro warnings was not such a good idea, as the
Apple compiler flags redefine the _ast_int8_t macro right on the
command line, producing a warning for every cc invocation.

(cherry picked from commit 929930224f898cb1371471fe554fabb73b31d11f)
2020-06-12 01:45:16 +02:00
Martijn Dekker
778b3da79a manual page: correct conditions under which shell is interactive
Only standard error needs to be on a terminal for a
shell to be interactive on init, not all output.

See sh_main() in src/cmd/ksh93/sh/main.c, under
"/* decide whether shell is interactive */".

Also, tcgetattr is not a syscall, so its manual page is
tcgetattr(3), not tcgetattr(2).

(cherry picked from commit 97f8bdb08650fd63f8e125257a86f5e6035fbdfa)
2020-06-12 01:45:16 +02:00
Martijn Dekker
d8a2b4fa6d manual page: fix documentation of default path
It didn't mention that the default path is obtained from the
operating system where available, and that the default string
documented is only a fallback (which, btw, should never occur on
modern systems).

See:
e_defpath[] in src/cmd/ksh93/data/msg.c
defpath_init() in src/cmd/ksh93/sh/path.c

src/cmd/ksh93/sh.1:
- Add a mention that the default path is equal to the output of
  ksh's 'getconf PATH' builtin command, unless that fails.

(cherry picked from commit 12b8dc54626a14171d3671a26041733a32e0e07d)
2020-06-12 01:45:16 +02:00
Martijn Dekker
7a421ba57f INIT: tweak cc.{darwin,freebsd}; add cc.openbsd
(cherry picked from commit a1d8ff6faca522a29161582952e232afc76fd643)
2020-06-12 01:45:16 +02:00
Martijn Dekker
8e97419b0b Fix ${.sh.subshell} counter to actually count level of subshells
This counter is documented as follows:
"The current depth for subshells and command substitution."

But before this commit, the actual behaviour was that the counter
was reset to zero whenever a subshell forked for any reason: a
pipe, background job, running 'ulimit', redirecting stdout in a
command substitution, and more. This behaviour was:

1. Not consistent with the documentation. Non-forked (a.k.a.
   virtual) subshells are an internal implementation detail which
   scripts should not have to be concerned with. The manual page
   doesn't mention them at all.

2. Inherently broken. Since a subshell may fork for any number of
   reasons, even mid-run, and those reasons may change with
   bugfixes and further development, scripts have never actually
   been able to rely on the value of ${.sh.subshell}.

So, this commit fixes the counter to count the levels of all
subshells, both virtual and forked.

src/cmd/ksh93/sh/xec.c: _sh_fork():
- Increase ${.sh.subshell} whenever we fork.

src/cmd/ksh93/sh/subshell.c:
- sh_subfork():
  * Fix comment to properly explain what it does. It doesn't
    "create" a subshell, it forks off an existing virtual subshell.
  * Don't zero ${.sh.subshell}. Instead, since sh_fork() increases
    it but we're forking an existing subshell, undo the increase.
- sh_subshell():
  * Remove 'int16_t subshell' variable. It was unnecessary and
    mostly unused. It was also the wrong type: it was assigned the
    value from shp->subshell which is of type short.
  * Increase and decrease the level of virtual subshells and
    ${.sh.subshell} independently.

src/cmd/ksh93/tests/variables.sh:
- Add regression tests for ${.sh.subshell} in virtual and forked
  subshells of several kinds: comsub, parentheses, pipe, bg job.
- Undo wrong error test count fix from 04b4aef0.

(cherry picked from commit a0e0e29e7e0dbf21e4b3958ae02bde6665fb2696)
2020-06-12 01:45:16 +02:00
Martijn Dekker
6c68b53170 For consistency & greppability: global replace "sub-shell" => "subshell"
(cherry picked from commit 25eeb9bcdc0a23a66765fd3e5d7e36337da65051)
2020-06-12 01:45:16 +02:00
Martijn Dekker
8b07d2a011 Fix various crashes by removing invalid memccpy() use
The sfputr() function (put out a null-terminated string) contained
a use of memccpy() that was invalid and could cause crashes,
because the buffer it was copying into could overlap or even be
identical with the buffer being copied from.

Among (probably) other things, this commit fixes a crash in 'print
-v' (print a compound variable structure) on macOS, that caused the
comvar.sh and comvario.sh regression tests to fail spectacularly.
Now they pass.

Issue discovered and fixed by Kurtis Rader in the abandoned ksh2020
branch; this commit backports the fix. He wrote:

| #if _lib_memccpy && !__ia64 /* these guys may never get it right */
|
| The problem is that assertion is wrong. It implies that the libc
| implementation of memccpy() on IA64 is broken. Which is
| incorrect. The problem is the AST sfputr() function is depending
| on what is explicitly undefined behavior in the face of
| overlapping source and destination buffers.
| [...] Using memccpy() simply complicates the code and is unlikely
| to be measurably, let alone noticeably, faster.

Further discussion/analysis: https://github.com/att/ast/issues/78

src/lib/libast/sfio/sfputr.c:
- Remove memccpy use. Always use the manual copying loop.

(cherry picked from commit fbe3c83335256cb714a4aa21f555083c9f1d71d8)
2020-06-12 01:45:16 +02:00
Martijn Dekker
6f0e008cf7 Fix unsetting special vars in subshells (re: efa31503, 8b7f8f9b)
This fixes (or at least works around) a bug that caused special
variables such as PATH, LANG, LC_ALL, LINENO, etc. to lose their
effect after being unset in a subshell.

For example:
(unset PATH; PATH=/dev/null; ls); : wrongly ran 'ls'
(unset LC_ALL; LC_ALL=badlocale); : failed to print a diagnostic

This is yet another problem with non-forking/virtual subshells. If
you forced the subshell to fork (one way of doing this is using the
'ulimit' builtin, e.g. ulimit -t unlimited) before unsetting the
special variable, the problem vanished.

I've tried to localise the problem. I suspect the sh_assignok()
function, which is called from unall(), is to blame. This function
is supposed to make a copy of a variable node in the virtual
subshell's variable tree. Apparently, it fails to copy the
associated permanent discipline function settings (stored in the
np->nvfun->disc pointer) that gave these variables their special
effect, and which survive unset. However, my attempts to fix that
have been unsuccessful. If anyone can figure out a fix, please send
a patch/pull request!
Data point: This bug existed in 93u 2011-02-08, but did not yet
exist in M-1993-12-28-s+. So it is a regression.

Meanwhile, pending a proper fix, this commit adds a safe
workaround: it forces a non-forked subshell to fork before
unsetting such a special variable.

src/cmd/ksh93/bltins/typeset.c: unall():
- If we're in a non-forked, non-${ ...; } subshell, then before
  unsetting any variable, check for variables with internal
  trap/discipline functions, and call sh_subfork() if any are
  found. To avoid crashing, this must be done before calling
  sh_pushcontext(), so we need to loop through the args separately.

src/cmd/ksh93/tests/variables.sh:
- Remove the 'ulimit' that forced the fork; we do this in C now.

(cherry picked from commit 21b1a67156582e3cbd36936f4af908bb45211a4b)
2020-06-12 01:45:16 +02:00
Martijn Dekker
04722950bb tests/variables.sh: fix subshell error count, & another xtrace caught in comsub
(cherry picked from commit 04b4aef0cf14d255ee27305f1458b34a1d3b8b6c)
2020-06-12 01:45:15 +02:00
Martijn Dekker
b6b8b522a7 regress tests: remove use of unportable direct paths to commands
Many tests used direct paths to some commands, mostly /bin/echo and
/bin/cat. This is unportable (breaks on e.g. NixOS).
The correct way is to obtain the direct path using 'whence -p'.

There was also one use of '/usr/bin/pstack' in tests/comvario.sh
that seemed bogus. Apparently this was supposed to analyse a core
file after a crash. Even on Solaris and Linux, where that command
exists, the argument is documented to be a PID, not a core file. If
this ever worked anywhere, then it was system-specific enough to be
useless here, so I've removed it.

(cherry picked from commit 4563b8bc651cd9cb18dc73f56a041f7ac5534395)
2020-06-12 01:45:15 +02:00
Martijn Dekker
3552a2bafd Restore building on old Mac OS X (Darwin) with GCC (re: e74e98b8)
In making ksh build on new macOS, it stopped building on old Mac OS
X (old gcc-based Darwin). There is no real reason for this. We can
just restore the old cc wrapper script and use it if an old gcc
compiler is detected.

This is only tested on Mac OS X 10.3 on my old Power Mac G5 so far.
But at least that allows me to test fixes on that platform. Unusual
platforms sometimes expose corner case bugs...

bin/package, src/cmd/INIT/package.sh:
- If /usr/bin/cc is GCC, change 'darwin' host name to 'darwin_old'.
  This removes the long-obsolete 'darwin7' host name.

src/cmd/INIT/cc.darwin_old:
- Restore the old cc.darwin script for darwin_old hosts.

(cherry picked from commit 93d4c6497ea8e9cc9f4977b75d06a673a2229f80)
2020-06-12 01:45:15 +02:00
Martijn Dekker
794d1c8601 shtests: report signal when a test crashes
When a test aborted due to a signal, the >256 exit code signifying
the signal was incorrectly reported as the number of errors.

src/cmd/ksh93/tests/shtests:
- For $? > 256, obtain and report the signal name using 'kill -l'.

(cherry picked from commit a7d8ae628e228fc3cadcf977fbffc87b90c7bc53)
2020-06-12 01:45:15 +02:00
Martijn Dekker
21f281a5fa tests/variables.sh: update virtual subshell failure TODO
Namerefs aren't broken in virtual/non-forked subshells after all
(phew). It is changing the locale that is somehow broken.

src/cmd/ksh93/tests/variables.sh:
- Pending further investigation, update the TODO and don't fork the
  subshell until actually needed.

(cherry picked from commit efa3150396b383b6a68b2df45eab9005593b2e42)
2020-06-12 01:45:15 +02:00
Martijn Dekker
759157bdb2 Fix hang in unsetting functions in subshells (re: dde38782)
This fixes a really stupid bug in my own code for unsetting a
function in a subshell. The algorithm for walking through the
subshell tree was broken, resulting in an infinite loop if there
were multiple levels of subshell.

src/cmd/ksh93/bltins/typeset.c:
- Correct the subshell function tree walk that deletes functions
  from zombie parent scopes.

src/cmd/ksh93/tests/subshell.sh:
- Add a regression test for setting and unsetting identically named
  functions in multiple levels of subshell.

(cherry picked from commit 972a7999c7f16469138daf3d86dfd6c0db3f4879)
2020-06-12 01:45:15 +02:00
Martijn Dekker
1026006db3 Fix BUG_KBGPID: $! was not updated under certain conditions
The $! special parameter was not set if a background job
(somecommand &) or co-process (somecommand |&) was launched as the
only command within a braces block with an attached redirection,
for example:
	{
		somecommand &
	} >&2
With the bug, $! was unchanged; now it contains the PID of
somecommand.

Ref.: https://github.com/att/ast/issues/1357

src/cmd/ksh93/sh/parse.c: item():
- When processing redirections following a compound command, always
  create a parent node with the TSETIO (I/O redirection) token.
     Before this commit, if the last command was of type TFORK (and
  the last command only tested as TFORK if the bg job or coprocess
  was the only command in a braces block, because the ksh parser
  optimises away the braces in that case), then the parent node was
  created with the TFORK token instead.
     I have no idea what David Korn's intention was with that, but
  this is clearly very wrong. Creating another TFORK node when
  parsing the redirection caused sh_exec() in sh/xec.c to execute
  the redirection in an extra forked, non-background subshell.
  Since redirections are executed before anything else, this
  subshell is what then launched the background job between the
  braces, so $! (a.k.a. shp->bckpid) was updated in that subshell
  only, and never in the main shell. The extra subshell also
  prevented the background job from being noticed by job control
  on interactive shells.
     So, the fix is simply to remove the broken test for TFORK.

src/cmd/ksh93/tests/variables.sh:
- Add regression tests for a bg job and a co-process as the only
  command within a braces block with attached redirection.

(cherry picked from commit ffe5df30e69f7b596941a98498014d8e838861f2)
2020-06-12 01:45:15 +02:00
Martijn Dekker
a9351320ed tests/variables.sh: fix problems with tracing ('bin/shtests -x')
src/cmd/ksh93/tests/variables.sh:
- Unset -x in a command substitution that redirects stderr to
  stdout; this caused a spurious failure with tracing active.
- Execute the nameref tests in a subshell. They modified LINENO, so
  that all the line numbers after this test were traced and/or
  reported as 'foo'.
  . This exposed a bug in namerefs: this is yet another thing that
    is broken in non-forked/virtual subshells! That is for another
    commit. For now, fork the subshell and leave a TODO.

(cherry picked from commit 8b7f8f9b14523a66bdf337612daef2501c2bb5ba)
2020-06-12 01:45:15 +02:00
Martijn Dekker
80126062cc tests/bracket.sh: don't test r/w perms as root; fix typos
src/cmd/ksh93/tests/bracket.sh:
- -r and -w are always true when running as root, so skip these.
- Fix several typos in the [[ tests (apparent copy/paste errors).

(cherry picked from commit b9325e9753b38f087d0c5501d474f7d1f15c4d36)
2020-06-12 01:45:15 +02:00
Martijn Dekker
e1ef18c8ef tests/builtin.sh: don't use unportable 'seq' (is not on OpenBSD)
(cherry picked from commit c9f6c148bff1fe82cb575d55467f68f2bef939ff)
2020-06-12 01:45:15 +02:00
Martijn Dekker
eee47df423 Fix handling of skipped directories when autoloading functions
Fix a bug in autoloading functions. Directories in the path search
list which should be skipped (e.g. because they don't exist) did
not interact correctly with autoloaded functions, so that a
function to autoload was not always found.

Details:
https://github.com/att/ast/issues/1454

Fix backported (and cleaned up) from:
https://github.com/att/ast/commit/3bc58164

src/cmd/ksh93/sh/path.c:
- path_opentype(): Fix the path search loop so that entries marked
  with PATH_SKIP are handled correctly.

src/cmd/ksh93/tests/functions.sh:
- Add regression test verifying an autoloaded function with a PATH
  that triggered the bug.
  The bug in path_opentype() fixed by this commit may affect other
  scenarios but we know it affects autoloaded functions. Hence the
  test for that scenario.

(cherry picked from commit a27903165775309f4f032de5d42ec1785f14cfbc)
2020-06-12 01:45:15 +02:00
Martijn Dekker
482d1c3dd6 fix 24 more typos found with the help of codespell
(cherry picked from commit a92198bc5f196ec1b4a34dc042ff3a594e316ad7)
2020-06-12 01:45:15 +02:00
Martijn Dekker
7003aba487 Fix 'test'/'[' exit status >1 on error in arithmetic expression
Fix BUG_TESTERR1A: POSIX non-compliance of 'test'/'[' exit status
on error. The command now returns status 2 instead of 1 when given
an invalid number or arithmetic expression, e.g.: [ 123 -eq 123x ]

The problem was that the test builtin (b_test()) calls the generic
arithmetic evaluation subsystem (sh/arith.c, sh/streval.c) which
has no awareness of the test builtin. A simple solution would be to
always make the arithmetic subsystem use an exit status > 1 for
arithmetic errors, but globally changing this may cause backwards
compatibility issues. So it's best to change the behaviour of the
'test' builtin only. This requires the arithmetic subsystem to be
aware of whether it was called from the 'test' builtin or not. To
that end, this commit adds a global flag and overrides the
ERROR_exit macro where needed.

src/cmd/ksh93/include/defs.h,
src/cmd/ksh93/sh/defs.c:
- Declare and initialise a global sh_in_test_builtin flag.
- Declare internal function for ERROR_exit override in test.c.

src/cmd/ksh93/bltins/test.c:
- Add override for ERROR_exit macro using a function that checks if
  the exit status is at least 2 if the error occurred while running
  the test builtin.
- b_test(): Set sh_in_test_builtin flag while running test builtin.

src/cmd/ksh93/sh/arith.c,
src/cmd/ksh93/sh/streval.c:
- Override ERROR_exit macro using function from test.c.

src/cmd/ksh93/tests/bracket.sh:
- Add regression test verifying status > 1 on arith error in test.

(cherry picked from commit 5eeae5eb9fd5ed961a5096764ad11ab870a223a9)
2020-06-12 01:45:15 +02:00
Martijn Dekker
ec888867fd Fix unsetting aliases in subshells
Aliases can now be correctly unset within subshell environments
(such as ( ... ), $(command substitutions), etc), as well as
non-subshell "shared" command substitutions (${ ...; }). Before,
attempts to unset aliases within these were silently ignored.

Prior discussion: https://github.com/att/ast/issues/108

Subshell alias trees are only referenced in a few places in the
code, *and* have always been broken, so this commit gets rid of the
whole notion of a subshell alias tree. Instead, there is now just
one flat alias tree, and subshells fork into a separate process
when aliases are set or unset within them. It is not really
conceivable that this could be a performance-sensitive operation,
or even a common one, so this is a clean fix with no downside.

src/cmd/ksh93/include/defs.h:
- Remove sh_subaliastree() definition.

src/cmd/ksh93/sh/subshell.c:
- Remove salias element (pointer to subshell alias tree) from
  subshell struct.
- Remove sh_subaliastree() function.
- sh_subshell(): Remove alias subshell tree cleanup.

src/cmd/ksh93/bltins/typeset.c:
- b_alias(): If in subshell, fork before setting alias.
- b_unalias(): If in subshell, fork before unsetting alias.
- unall(): Remove sh_subaliastree() call.

src/cmd/ksh93/sh/name.c:
- nv_open(): Remove sh_subaliastree() call.

src/cmd/ksh93/tests/subshell.sh:
- Add regression tests for unsetting or redefining aliases within
  subshells.

(cherry picked from commit 12a15605b9521a2564a6e657905705a060e89095)
2020-06-12 01:45:14 +02:00
Martijn Dekker
047cb3303c Fix redefining & unsetting functions in subshells (BUG_FNSUBSH)
Functions can now be correctly redefined and unset in subshell
environments (such as ( ... ), $(command substitutions), etc).
Before this fix, attempts to do this were silently ignored (!!!),
causing the wrong code (i.e.: the function by the same name from
the parent shell environment) to be executed.

Redefining and unsetting functions within "shared" command
substitutions of the form '${ ...; }' is also fixed.

Prior discussion: https://github.com/att/ast/issues/73

src/cmd/ksh93/sh/parse.c:
- A fix from George Koelher (URL above). He writes:
  | The parser can set t->comnamp to the wrong function.
  | Suppose that the shell has executed
  |     foo() { echo WRONG; }
  | and is now parsing
  |     (foo() { echo ok; } && foo)
  | The parser was setting t->comnamp to the wrong foo. [This
  | fix] doesn't set t->comnamp unless it was a builtin. Now the
  | subshell can't call t->comnamp, so it looks for foo and finds
  | the ok foo in the subshell's function tree.

src/cmd/ksh93/bltins/typeset.c:
- Unsetting functions in a virtual/non-forked subshell still
  doesn't work: nv_open() fails to find the function. To work
  around this problem, make 'unset -f' fork the subshell into its
  own process with sh_subfork().
- The workaround exposed another bug: if we unset a function in a
  subshell tree that overrode a function by the same name in the
  main shell, then nv_delete() exposes the function from the main
  shell scope. Since 'unset -f' now always forks a subshell, the
  fix is to simply walk though troot's parent views and delete any
  such zombie functions as well. (Without this, the 4 'more fun'
  tests in tests/subshell.sh fail.)

src/cmd/ksh93/sh/subshell.c: sh_subfuntree():
- Fix function (re)definitions and unsetting in "shared" command
  substitutions of the form '${ commandlist; }' (i.e.: if
  sp->shp->subshare is true). Though internally this is a weird
  form of virtual subshell, the manual page says it does not
  execute in a subshell (meaning, all changes must survive it), so
  a subshell function tree must not be created for these.

src/cmd/ksh93/tests/subshell.sh:
- Add regression tests related to these bugfixes. Test unsetting
  and redefining a function in all three forms of virtual subshell.

(cherry picked from commit dde387825ab1bbd9f2eafc5dc38d5fd0bf9c3652)
2020-06-12 01:45:14 +02:00
Martijn Dekker
6e90d4d76c tests/path.sh: if root, skip tests involving unreadable scripts
These always fail when running as root, as root can access files
regardless of permission bits.

(cherry picked from commit a821fe13906ac8ef56162bebd7c3e976b973f91c)
2020-06-12 01:45:14 +02:00
Martijn Dekker
62f8e744f1 tests/variables.sh: minor fix in failure error msg
(cherry picked from commit bdcbcf42415aaf120a4e3a98fd4af1f8b810018f)
2020-06-12 01:45:14 +02:00
Martijn Dekker
593a5a8b7f Patch vulnerability CVE-2019-14868
Certain environment variables were interpreted as arithmetic
expressions on startup, leading to code injection.

Ref.:
https://bugzilla.redhat.com/show_bug.cgi?id=1757324
c7de8b6412

(cherry picked from commit ee6b001d0611ad2e00b6da2c2b42051995c0a678)
2020-06-12 01:45:14 +02:00
Martijn Dekker
c1dae413d2 shtests: don't require specifying .sh extension for test script
It was annoying me that I always had to type out the .sh in
'shtests builtins.sh', etc. to execute a specific regression test
script. All the test scripts end in .sh, so this is superflous.

src/cmd/ksh93/tests/shtests:
- Add .sh to test script arguments if not already present.

(cherry picked from commit d780e701fbf6f27b6e79f88542a3175bf5dd85e9)
2020-06-12 01:45:14 +02:00
Martijn Dekker
e999f6b169 Fix truncating of files with <>;file combined with <#pattern
The issue with truncating files was caused by out-of-sync streams.
Details and discussion: https://github.com/att/ast/issues/61

src/cmd/ksh93/sh/io.c: sh_iorestore():
- To be safe, sync all streams before restoring file descriptors.

src/cmd/ksh93/tests/io.sh:
- Add two regression tests for truncating files with this
  combination of redirections.
- The second test, which invokes a -c script, is disabled for now
  as this triggers another corner case bug involving the SH_NOFORK
  optimisaton for -c scripts. That fix is for another commit.

(cherry picked from commit 18fb64840365c2ff4608188e5487bd79d08f67d1)
2020-06-12 01:45:14 +02:00
Martijn Dekker
a638e724d0 INIT/cc.darwin: revert inadvertent change in SHOPT_SPAWN
(cherry picked from commit def69c3315d1d357b3e067a186913991ea2abdf3)
2020-06-12 01:45:14 +02:00
Martijn Dekker
60516872de tests/io.sh: Update after BUG_PUTIOERR and BUG_REDIRIO fixes
src/cmd/ksh93/tests/io.sh:
- After BUG_REDIRIO was fixed in 29afc16c, '<>' now defaults to
  '0<>' instead of '1<>', as POSIX specifies. Update '<>' to '1<>'.
- After BUG_PUTIOERR was fixed in 9011fa93, one 'print' command
  with pipe buffering disabled (piped into 'read -n3') printed an
  expected I/O error to standard error. Redirect this to /dev/null.

(cherry picked from commit d4b6510fdf155a3d75a98860a09c0ebedb6c93d2)
2020-06-12 01:45:14 +02:00
Martijn Dekker
952944197f Fix bugs in testing if a parameter is set
This fixes three related bugs:
1. Expansions like ${var+set} remained static when used within a
   'for', 'while' or 'until' loop; the expansions din't change
   along with the state of the variable, so they could not be used
   to check whether a variable is set within a loop if the state of
   that variable changed in the course of the loop. (BUG_ISSETLOOP)
2. ${IFS+s} always yielded 's', and [[ -v IFS ]] always yielded
   true, even if IFS is unset. (BUG_IFSISSET)
3. IFS was incorrectly exempt from '-u' ('-o nounset') checks.

src/cmd/ksh93/sh/macro.c: varsub():
- When getting a node pointer (np) to the parameter to test,
  special-case IFS by checking if it has a value and not setting
  the pointer if not. The node to IFS always exists, even after
  'unset -v IFS', so before this fix it always followed the code
  path for a parameter that is set. This fixes BUG_IFSISSET for
  ${IFS+s} and also fixes set -u (-o nounset) with IFS.
- Before using the 'nv_isnull' macro to check if a regular variable
  is set, call nv_optimize() if needed. This fixes BUG_ISSETLOOP.
  Idea from Kurtis Rader: https://github.com/att/ast/issues/1090
  Of course this only works if SHOPT_OPTIMIZE==1 (the default),
  but if not, then this bug is not triggered in the first place.
- Add some comments for future reference.

src/cmd/ksh93/bltins/test.c: test_unop():
- Fix BUG_IFSISSET for [[ -v IFS ]]. The nv_optimize() method
  doesn't seem to have any effect here, so the only way that I can
  figure out is to special-case IFS, nv_getval()'ing it to check if
  IFS has a value in the current scope.

src/cmd/ksh93/tests/variables.sh:
- Add regression tests for checking if a varariable is set within a
  loop, within and outside a function with that variable made local
  (to check if the scope is honoured). Repeat these tests for a
  regular variable and for IFS, for ${foo+set} and [[ -v foo ]].

(cherry picked from commit a2cf79cb98fa3e47eca85d9049d1d831636c9b16)
2020-06-12 01:45:14 +02:00
Martijn Dekker
2887378ae3 INIT/cc.darwin: suppress another annoying compiler warning
src/cmd/INIT/cc.darwin:
- Since the flags added from Apple's ksh-27.tar.gz Makefile
  explicitly redefine a macro, let's disable the warning on
  redefined macros.

(cherry picked from commit 4b21a0abce8406e82d3afa4a68ef6bb56d98c797)
2020-06-12 01:45:14 +02:00
Martijn Dekker
c9ccee86bb Fix 'command -p' by fixing initialisation of default PATH variable
'command -p' was broken for non-interactive shells as the variable
used to store the default system PATH, std_path, was not
initialised correctly. For instance:
	$ ksh -c 'command -p ls'
	ksh: ls: not found
This fix by Siteshwar Vashisht is backported from ksh2020.
Ref.:
https://github.com/att/ast/issues/426
https://github.com/att/ast/pull/448

src/cmd/ksh93/sh/path.c:
- Correctly initialise std_path (the default PATH) when ksh is
  started as a non-interactive shell.

src/cmd/ksh93/sh.1:
- Fix vague explanation of 'command -p'.

src/cmd/ksh93/tests/path.sh:
- Add regression test.

(cherry picked from commit a76439d60b70c18cf44d84c1962fcd8df84c947c)
2020-06-12 01:45:14 +02:00
Martijn Dekker
f35e7ecd1d INIT/cc.darwin: default to -Os (small code) like Apple does
(cherry picked from commit 2210ff9026ca3f05dc88988c72f56eea195753cc)
2020-06-12 01:45:14 +02:00
Martijn Dekker
9f6dd1ea73 ksh93/sh.1: say that ${.sh.subshell} only counts virtual subshells
${.sh.subshell} only counts the nesting level of virtual (non-forked)
subshell environments relative to the current process, whether that
is the main shell environment or a real (forked) subshell.

This means ${.sh.subshell} is not sufficient to test if your code
is running in a subshell environment, so it's important to mention
this in the manual.

E.g.:
    (echo ${.sh.subshell}; ulimit -t 1; echo ${.sh.subshell}); :
outputs 1 followed by 0.

(cherry picked from commit 63dad8863fd26bf3aa4d7a1cf60b743f4169f7c4)
2020-06-12 01:45:14 +02:00
Martijn Dekker
d10eab988a Regression test suite: bugfix: accurately report number of errors
The number of errors in each tests/*.sh test set is reported using
its exit code (up to 125). The main test script saves this code in
$e to report the number of errors. But if a set had errors, $e was
then erroneously overwritten before reporting the number of errors,
so it was always 1.

src/cmd/ksh93/tests/shtests:
- Don't overwrite $e with the exit code of ((e == 0)).

(cherry picked from commit b9ab95488b23167316f5b21f338368c9490ebc50)
2020-06-12 01:45:14 +02:00
Martijn Dekker
75fc493e7d sh/suid_exec.c: fix 2 confusing typos in comments
(cherry picked from commit 6cccaedd91e4309b542b8a17c8318f3bff9511b0)
2020-06-12 01:45:14 +02:00
Martijn Dekker
412cd96dc1 fix 5 more typos: incorrect "than"
(cherry picked from commit 7e2e4651d2dd5884dd3ea06fc8df4dc45ec9bfb5)
2020-06-12 01:45:13 +02:00
Martijn Dekker
cafe33f048 Fix 'test -t 1' in $(command substitutions)
Standard output (FD 1) tested as being on a terminal within a
command substitution, which makes no sense as the command
substitution is supposed to be catching standard output.
    ksh -c 'v=$(echo begincomsub
                [ -t 1 ] && echo oops
                echo endcomsub)
            echo "$v"'
This should not output "oops".

This is one of the many bugs with ksh93 virtual (non-forked)
subshells. On the abandoned Vashist/Rader ksh2020 branch, this bug
was fixed by changing quite a lot of code, which introduced and/or
exposed another bug:
	https://github.com/att/ast/issues/1079
	https://github.com/att/ast/commit/8e1e405e
	https://github.com/att/ast/issues/1088
That issue was unresolved when the ksh2020 branch was abandoned.

The safer and more conservative fix is simply forcing the subshell
to fork if we're in a non-forked command substitution and testing
'-t 1'. It is hard to imagine a situation where this would cause a
noticable performance hit.

Note that this fix does not affect ksh93-specific "shared"
non-subshell ${ command substitutions; } which are executed in the
main shell environment, so that variables survive, etcetera.
'test -t 1' continues to wrongly return true there, but command
substitutions of that form cannot be forked because that would
defeat their purpose.

src/cmd/ksh93/bltins/test.c:
- Fix 'test -t 1', '[ -t 1 ]' and '[[ -t 1 ]]' by forking the
  current subshell if it is a virtual/non-forked subshell
  (shp->subshell), and a command substitution (shp->comsub), but
  NOT a "shared" ${ command substitution; } (!shp->subshare).

src/cmd/ksh93/tests/bracket.sh:
- Add two regression tests for this issue, which were adapted from
  the Vashist/Rader ksh2020 branch.

NEWS, src/cmd/ksh93/include/version.h:
- Update.

(cherry picked from commit b8ef05e457ead65b83417699b8dd8632f855e2fa)
2020-06-12 01:45:13 +02:00
Martijn Dekker
b87a7cabc5 tests/locale.sh: fix test that depended on 'od' whitespace output
Different implementations of the 'od' command may legitimately vary
the whitespace they output between fields. One of the regression
tests checked 'od' output without tolerating whitespace varieties,
which is not portable. For example, the BSD 'od' implementation
outputs more whitespace than the variant used to write the test.

src/cmd/ksh93/tests/locale.sh:
- In test "incorrect string from printf %q", use 'awk' to eliminate
  whitespace from 'od' output before checking results.

(cherry picked from commit 7aa830bd3a2284f7228ee7189f5671749c3f2682)
2020-06-12 01:45:13 +02:00